Professor Curie is using the radioactive isotope Francium-223 in her research. This

isotope has a half-life of 22 minutes, which means that every 22 minutes the sample has

half the radioactivity it did in the previous interval. If Professor Curie has 15 grams of

Francium-223, which explicit formula describes how the isotope decays?

Answers

Answer 1

This formula describes how the amount of Francium-223 (N(t)) decays over time (t). The initial amount of Francium-223 is 15 grams, and each 22 minutes the amount is halved.

Step 1: Start with the formula

N(t) = 15 * (1/2)^(t/22).

Step 2: Substitute the value for N(t). For example, if you want to find the amount of Francium-223 after 44 minutes,

N(44) = 15 * (1/2)^(44/22).

Step 3: Calculate the fraction (1/2)^(44/22). This is equal to (1/2)^2, or 1/4.

Step 4: Multiply the initial amount of Francium-223 (15) by the fraction (1/4). The result is

15 * (1/4) = 3.75 grams.

The formula N(t) = 15 * (1/2)^(t/22) describes how the amount of Francium-223 (N(t)) decays over time (t). The initial amount of Francium-223 is 15 grams, and each 22 minutes the amount is halved. To calculate the amount of Francium-223 after a certain time, substitute the value for N(t). Then calculate the fraction (1/2)^(t/22) and multiply it by the initial amount of Francium-223 (15). The result is the amount of Francium-223 after the specified time. For example, after 44 minutes, the amount of Francium-223 is 15 * (1/4) = 3.75 grams.

Learn more about amount here

https://brainly.com/question/28970975

#SPJ4


Related Questions

triangle ABC has a perimeter 22cm
AB=8cm
BC=5cm
by calculation, deduce whether ABC is a right angle triangle? ​

Answers

perimeter = AB + AC + BC
22 = 8 + AC + 5
AC = 9

from phitagoras rule it states that
if ABC is a right angle then

9^2 = 8^2 + 5^2

81≠89

so its not right angelic

- 2 3/4-(-1 1/2)+(-5/6)-(3/8)-(+4 2/3)

Answers

Answer:

-57/8

Step-by-step explanation:

- 2 3/4 - (-1 1/2) + (-5/6) - (3/8) - (+4 2/3)

= -7.125

plz answer will give 5* brainliest and thanks plz plz plz ur being timed xD

Answers

Answer:

y = 1/2x + 0

Step-by-step explanation:

i have a question can yall help me

Answers

Answer:

yeah what is it

Step-by-step explanation:

We'll try our level best to help u ...

6. It took Mrs. Whitaker's class 4 hours to build a snowman.
They decided to build a second snowman, but this time it took
only half the time it took to build the first one. What was the
total amount of time to build both?

Answers

The two snowmen took a combined six hours to construct, compared to the four hours it took to construct the first.

what is equation ?

An equation is a mathematical formula that connects two assertions using the equal sign (=) to denote equivalence. For instance, an equal sign separates the components 3x + 5 and 14 in the equation 3x + 5 = 14. A mathematical formula is used to express the connection between two phrases on either side of a letter. Frequently, there is just one variable, which is also the symbol. for example, 2x - 4 = 2.

given

1st snowman took time t = 4 hours

2nd snowman take half of the first t / 2 = 2 hours

so total time

= t + t/2

= 4 + 2

= 6 hours

The two snowmen took a combined six hours to construct, compared to the four hours it took to construct the first.

To know more about equation visit:

https://brainly.com/question/649785

#SPJ1

(-2) (-3) less greater than equal than 8- (-2)

Answers

The true statement is 6 less than 10

How to determine the true statement

From the question, we have the following parameters that can be used in our computation:

(-2) (-3) less greater than equal than 8- (-2)

We start by evaluating each expression

So, we have the following representation

(-2) (-3) = 6

8- (-2) = 10

Substitute the known values in the above equation, so, we have the following representation

6 less greater than equal than 10

6 is less than 10

So, we have

6 less than 10

Read more about inequality at

https://brainly.com/question/25275758

#SPJ1

(2, -4) and (-3, -3) write the linear equation in slope intercept form given the following

Answers

Answer:

y = -1/5x - 3.6

Step-by-step explanation:

(2, -4) and (-3, -3)

m = -3+4/ -3-2

m = 1/-5

m = -1/5

y = -1/5x + b

-4 = -1/5(2) + b

-4 = -0.4 + b

b = -3.6

y = -1/5x - 3.6

How many times greater is 904.32 than 113.04!!!!
PLS HELP

Answers

Answer: 8 times greater

Step-by-step explanation: divide them 904.32/113.04 and you'll get 8

Find the greatest common factor of 21, 35, 49.

Answers

Answer:

You can use formulas for finding them but this is my best method.

Step-by-step explanation:

21=3×7

35=5×7

49=7×7

Finding the hcf or gcf you will first find the common numbers between all the prime factors which is 7.

Therefore gcf of 21,35 and 49 is 7

What is the equation for the linear relationship in slope intercept form?

Answers

Answer:

y=-2/3x+4

Step-by-step explanation:

slope intercept form = y=mx+b

y=-2/3x+4

Find an equation of the circle that has center -(-5,6) and passes through (-1,1).

Answers

Answer:

[tex](x+5)^2+(y-6)^2=41[/tex]

Step-by-step explanation:

Hi there!

Equation of a circle: [tex](x-h)^2+(y-k)^2=r^2[/tex] where the circle is centered at [tex](h,k)[/tex] and r is the radius

1) Plug in the center (-5,6)

[tex](x-(-5))^2+(y-6)^2=r^2\\(x+5)^2+(y-6)^2=r^2[/tex]

2) Plug in the given point (-1,1) and solve for r²

[tex](-1+5)^2+(1-6)^2=r^2\\(4)^2+(-5)^2=r^2\\16+25=r^2\\41=r^2[/tex]

Therefore, r² is 41. Plug this back into [tex](x+5)^2+(y-6)^2=r^2[/tex]:

[tex](x+5)^2+(y-6)^2=41[/tex]

I hope this helps!

PLEASE PLEASE HELP!!
Need it by the end of the night!
4.
Kelly Waxman's annual salary is $30,000. She takes
a married exemption. Using the graduated income
tax rates in the figure on the right, find the annual
state tax withheld. (Section 2-3)
a. $1,877. 21
c. $1,877. 90
b. $2,159. 85
d. $1,662. 50
Personal Exemptions
Single
$1,500
Married
$3,000
Each Dependent
$ 750
State Tax
Annual Gross Pay Tax Rate
First $3,500
3%
Next $3,500
4. 5%
Over $7,000
7%​

Answers

The annual state tax withheld for Kelly Waxman would be 1,662.50 dollars.

Therefore the answer is d) $1,662.50.

Here is the breakdown of the calculation:

Kelly's salary of $30,000 minus the married exemption of $3,000 = $27,000

The first $3,500 are taxed at 3%, which is

= 0.03×3500

= $105

The next $3,500 are taxed at 4.5%, which is

= 0.045×3500

= $157.50

The remaining $27,000 - $3,500 - $3,500 = $20,000 are taxed at 7%, which is

= 0.07×20000

= $1,400

Adding all three amounts together: $105 + $157.50 + $1,400 = $1,662.50. It is the annual state tax withheld.

To know more on tax

https://brainly.com/question/10114457

#SPJ4

I’ll brainliest you please help me

Answers

Answer:

a. 15 inches

Step-by-step explanation:

Pythagorean theorem:

a² + b² = c²

a² = 9in

b² = 12in

9² + 12² = c²

9² = 81

12² = 144

81 + 144 = 225

c² = 225

simplify = √225

√225 = 15

X=15
We know this because we can use the Pythagorean theorem to answer the question.

a^2+b^2=c^

12^2 +9^2=c^

225=c^2

And the answer we get is 15

The teacher gave a true and false quiz where P(true) = 0.8 for each question. Interpret the likelihood that the first question will be true.

Likely
Unlikely
Equally likely and unlikely

Answers

Answer: 0.8 what?

Step-by-step explanation:

prolly likely

A rectangular garden is divided into four sections. Some dimensions are shown in the diagram, and the distance from point A to C is 16ft. What is the distance from point A to B?

A. 8ft
B. 7ft
C. 9ft
D. 6ft

Answers

7ft is the answer in this case

Find the equation of the line. ​

Answers

Answer:

[tex]y=\frac{9}{10}x-\frac{7}{5}[/tex]

Step-by-step explanation:

Using the points [tex](-4,-5)[/tex] and [tex](6,4)[/tex], the slope is [tex]m=\frac{-5-4}{-4-6}=\frac{9}{10}[/tex].

Using point-slope form:

[tex]y+5=\frac{9}{10}(x+4) \\ \\ y+5=\frac{9}{10}x+\frac{18}{5} \\ \\ y=\frac{9}{10}x-\frac{7}{5}[/tex]

Which expression represents these words?

7 more than the product of 9 and 8

Answers

Answer:

7 + (9 * 8)

Step-by-step explanation:

You don't need parenthesis unless it helps you understand.

The expression is represent as 7 + (9 x 8).

Here,

The condition is given as,

The expression is 7 more than the product of 9 and 8.

How to write an expression?

We write an expression by using numbers or variables and mathematical operators which are addition, subtraction, multiplication and division.

Now,

Product of 9 and 8 is written as 9 x 8.

Hence, 7 more than the product of 9 and 8 is written as;

⇒ 7 + (9 x 8)

The expression is represent as 7 + (9 x 8).

Learn more about to the write an expression visit:

https://brainly.in/question/17645770

#SPJ2

5 feet x 3 feet x 2 and 1/4

Answers

Answer:

3.1354776 m2

Step-by-step explanation:

Answer: 33.75

Step-by-step explanation:

5 times 3 is 15 and 15 times 2 1/4 is 33.75

How can you identify and write equivalent expressions?

Answers

You can identify equivalent expressions if one of the expressions can be written like the other and it is usually written by combining any like terms on each side of the equation such as x-terms with x-terms and constants with constants.

What is an Equivalent expression?

These are the type of expressions that have similar value or worth but do not look the same.

This type of expression can be identified if one of the expressions can be written like the other and example can be seen below:

3(x + 3) and 3x + 9

Read more about Equivalent expression here https://brainly.com/question/15775046

#SPJ1

PLEASE HELP WILL MARK BRAINIEST AND NO LINKS!!!!

Answers

Answer:

a. 5 seconds

b. 1 second

Step-by-step explanation:

Plug the values into the equation and solve for t.

[tex]f(t)=-16t^2+400\\f(t)=-16t^2+16[/tex]

A school is selling cookies as a fundraiser. Each box contains 10 cookies. Each student can sell 17 boxes of cookies. How many cookies can 11 students sell

Answers

11 students could sell 1870 cookies.

Explain about the expressions?

A statement, at least two variables or integers, and one or more arithmetic operations make up a mathematical expression. This mathematical operation enables the multiplication, division, addition, or subtraction of numbers.

Combining numbers, variables, and operators to represent something's value is known as a mathematical expression. Setting two expressions equal to one another creates an equation, a mathematical statement.

An expression is a collection of numbers, variables, and functions (such as addition, subtraction, multiplication or division etc.) Expressions and phrases are similar in certain ways. Language phrases can comprise actions on their own, but they do not make up complete sentences.

=  10 X 17

=  170 X 11

= 1870

To learn more about expressions refer to:

https://brainly.com/question/1859113

#SPJ4

PLEASE HELP BRANLIEST!!!!

Answers

Answer:

A. y = (x + 3)(x - 2)

Step-by-step explanation:

I used the points where the line crosses the x - axis. (0,-3 and 0,2).

Also, graph it. I use desmos.

Answer:

A)

Step-by-step explanation:

Graphed the equation

What is the solution to the system of equations?

Answers

Answer:

(2,5)

Step-by-step explanation:

First, we notice that

y = -x + 7

y = 2x + 1

Next, since both -x + 7 and 2x + 1 are equal to y, than by that logic it means

-x+7 = 2x+ 1

Add x to both sides

7 = 3x+1

Subtract 1 from both sides

6 = 3x

x = 2

Now that we solved x, let's plug x = 2 into either -x+7 or 2x + 1. Either way, both will have the same answer.

y = -x + 7

y = -(2) +7

y = 5

Therefore, the answer is

x= 2

y = 5

(2,5)

3 Select the correct answer. Which value of x makes this equation true? -5(x-20)=35 A. -11 B. 13 C.27 D.-3

Answers

The correct answer is D. -3. To find the value of x that makes this equation true, we need to solve for x. First, we can distribute the negative 5 on the left side of the equation to get: -5x + 100 = 35
Next, we can add 5x to both sides of the equation to get: 100 = 35 + 5x
Then, we can subtract 35 from both sides of the equation to get: 65 = 5x
Finally, we can divide both sides of the equation by 5 to get: x = 13
Since the question asks for the value of x that makes the equation true, the correct answer is x = -3.

Examine the given run chart or control chart and determine whether the process is within statistical control. If it is not, identify which of the three out-of-statistical-control criteria apply.

A. Process mean is not within statistical control. One of the points lies above the upper control limit.


B. Process mean is not within statistical control. There are points above and below the control limits.


C. Process mean is not within statistical control. There is an upward trend which is indicating an increase in variation.


D. Process mean is within statistical control.

Answers

Answer:

(B) Process mean is not within statistical control. There are points above and below the control limits. There is a shift upward.

Step-by-step explanation:

Gradpoint

Please help me on this

Answers

Answer:

A) 226.9

Step-by-step explanation:

tan80=x/40

Please help ASAP!

Write the recurring decimal 0.123 (1 and 3 being the repeated) as a fraction

Answers

The simplest exact fraction for the decimal number 0.123 is 1231000

Select all expressions that are equivalent to 3x - 2 (x - 4) - 1

Answers

Answer:

x+7

Step-by-step explanation:

Remove Parentheses

Collect like terms

Calculate

Answer: x+7

Step-by-step explanation: distribute the -2 first

3x - 2x + 8 - 1

simplify (combine like terms )

3x-2x= x

8-1= 7

x+7  

Hope this helps (^_^)

HELPPPPPP PLEASEeeeeeeeeeeeeee

Answers

Answer:

1/2

Step-by-step explanation:

-3x+5x-2>-4x+1

first, you will combine like terms. -3x+5x=2x.

2x-2>-4x+1

you need to move the variable to one side. So you will add 4x on both sides.

6x-2>1

You need to add 2.

6x>3.

Now you will divide both sides by 6 to get x by itself.

x> .5 or 1/2

pls barinliest

what is the next operation that should be done when evaluating this expression?
9-12+-2+3(-3)
a) 3(-3)=-9
b)-2+3=1
and if you dont mind showing how you did it so i can learn it thanks!

Answers

The next operation that should be done when evaluating this expression 9-12+-2+3(-3) is A. 3(-3)=-9

How to calculate the expression?

An expression is simply used to show the relationship between the variables that are provided or the data given regarding an information. In this case, it is vital to note that they have at least two terms which have to be related by through an operator. Some of the mathematical operations that are illustrated in this case include addition, subtraction, etc.

In this case, it should be noted that the expression given is written as 9-12+-2+3(-3). In PEDMAS, the first operation is parentheses. Therefore, the number on parentheses will be solved first.

In this case, the number in parentheses will be 3(-3). Therefore, the correct option is A.

Learn more about expressions on:

https://brainly.com/question/723406

#SPJ1

Other Questions
Which piece of text evidence BEST supports the statement thatno one thought Jacqueline would become a famous author? When you are dealing with regular text, abbreviations generally should beused:O A. whenever possible.B. when you're sure your readers will know what the abbreviationsstand for.O C. when your readers are unfamiliar with the abbreviations.O D. None of the above Do you think that manufacturers are responsible for the effects of the chemicals used in creating their products? What is the paradox in The Importance of Being Earnest? How many of the carbons in the following compound are chiral center(s)? A) 0 B) 1 C) 2 D) 3 E) 4 or more What would be the most likely cause of this genetic variation? PLEASE I WATED SO MUCH POINTS ON PPL GIVEING ME LINK SO PLEASE DONT GIVE LINKS PLEASE HELP ASAP!! CORRECT ANSWER ONLY PLEASE!!!Which expense can be paid for with a flexible spending account (FSA)?A. car insurance deductibleB. child careC. mortgage paymentD. unexpected home repair Analyzing Recall what you have read about the political ideals of the Enlightenment. Which of those ideals can you see in the second excerpt from Bolvars speech? Why does Bolvar mention them at this point?Source: Primary and Secondary SourcesActivity netw rksSimn Bolvar, An Address of Bolvar at the Congress of Angostura (February 15, 1819) (Find Online!) Please help :( how you do the bottom part What is the story Millicent about? UC is concerned with system performance in its contact center because the number of records has exceeded 40 million. What platform functionality might be affected by the number of contact records A shop has a sale of 15% off all items in stock. If the original price of a dress is 40 what would be its sale price? What was Mendel's initial question? Khan Academy Question pls answers only helppppppppppppppppppppppppppp meeeeeeeeeee find the area A large plane cruises at 530 miles per hour. What is the ratio, Unit Rate, and Rate? Answer this please.____ What metaphor does biss use to explain how herd immunity works? A state trooper used a radar gun to measure the speed (in miles per hour) of all the cars that drove past her stretch of highway in a twenty minute period. She separated the results by whether the cars were traveling northbound or southbound. The histograms show the speed of each car that she recorded.Which statement is an appropriate inference based on the median of each data set?Question 4 options:1.)The northbound cars were generally faster because the median for the northbound cars is less than the median for the southbound cars.2.)The northbound cars were generally faster because the median for the northbound cars is greater than the median for the southbound cars.3.)The southbound cars were generally faster because the median for the northbound cars is less than the median for the southbound cars.4.)The southbound cars were generally faster because the median for the northbound cars is greater than the median for the southbound cars.