6. Suppose that a password for a computer system must have at least 6, but no more than 9 characters, where each character in the password is a lowercase English letter, or an uppercase English letter, or a digit, or one of the five special characters *, <, >,!, and #.
(a) How many different passwords are available for this computer system?
(b) How many of these passwords contain at least one occurrence of at least one of the five special characters?
(c) Using your answer to part (b), determine how long it takes a hacker to try ev ery possible password, assuming that it takes one microsecond for a hacker to check each possible password.
Answers
a. There are 26 letters in the English alphabet, with two cases for each letter; 10 numerical characters in the range 0-9; and 5 special characters; thus a total of 26•2 + 10 + 5 = 67 characters.
Any character can be used more than once, so there are
67⁶ + 67⁷ + 67⁸ + 67⁹
or 27,618,753,243,839,080 total possible passwords.
b. If we require at least 1 special character, then there are 62 choices for each ordinary character we use and 5 for each special character.
Suppose we use a password of length 6. Then there are
62⁵•5¹ + 62⁴•5² + 62³•5³ + 62²•5⁴ + 62¹•5⁵ + 62⁰•5⁶
or
[tex]\displaystyle \sum_{k=1}^6 62^{6-k}\cdot5^k[/tex]
We count the longer passwords in a similar fashion:
[tex]\displaystyle \sum_{m=6}^9 \left(\sum_{k=1}^m 62^{m-k}\cdot5^k\right)[/tex]
or 1,206,930,268,794,100 total passwords
c. 1 second (s) is equal to 10⁶ microseconds (μs). If it takes 1 μs to try 1 password, then it would take
(1,206,930,268,794,100 passwords) • (1 μs / password) • (1 s / 10⁶ μs)
= 1,206,930,268.7941 s
= (1,206,930,268.7941 s) • (1 min / 60 s)
≈ 20,115,504.4799 min
≈ (20,115,504.4799 min) • (1 h / 60 min)
≈ 335,258.408 h
≈ (335,258.408 h) • (1 day / 24 h)
≈ 13,969.1003 days
≈ (13,969.1003 days) • (1 year / 365 days)
≈ 38.2715 years
Related Questions
A snack company makes packages of grapes and honeydew slices. The weight of an individual package of
grapes, G, is approximately Normally distributed with a mean of 3.25 ounces and a standard deviation of 0.91
ounces. The weight of an individual package of honeydew slices, H, is approximately Normally distributed with a
mean of 4.51 ounces and a standard deviation of 2.02 ounces. Assume G and H are independent random
variables. Let D=G-H. What is the probability that a randomly selected package of grapes weighs more than a
randomly selected package of honeydew slices?
O 0.127
O 0.230
0.284
0.334
Answers
Using the normal distribution, it is found that there is a 0.284 = 28.4% probability that a randomly selected package of grapes weighs more than a randomly selected package of honeydew slices.
In a normal distribution with mean [tex]\mu[/tex] and standard deviation [tex]\sigma[/tex], the z-score of a measure X is given by:
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
It measures how many standard deviations the measure is from the mean. After finding the z-score, we look at the z-score table and find the p-value associated with this z-score, which is the percentile of X. When two normal variables are subtracted, the mean is the subtraction of the means, while the standard deviation is the square root of the sum of the variances.In this problem, for each variable, [tex]\mu_G = 3.25, \sigma_G = 0.91, \mu_H = 4.51, \sigma_H = 2.02[/tex]
For the subtraction, we have that:
[tex]\mu_D = \mu_G - \mu_H = 3.25 - 4.51 = -1.26[/tex]
[tex]\sigma_D = \sqrt{\sigma_G^2 + \sigma_H^2} = \sqrt{0.91^2 + 2.02^2} = 2.2155[/tex]
The probability that a randomly selected package of grapes weighs more than a randomly selected package of honeydew slices is P(D > 0), which is 1 subtracted by the p-value of Z when X = 0.
[tex]Z = \frac{X - \mu}{\sigma}[/tex]
[tex]Z = \frac{0 - (-1.26)}{2.2155}[/tex]
[tex]Z = 0.57[/tex]
[tex]Z = 0.57[/tex] has a p-value of 0.7157.
1 - 0.715 = 0.284
0.284 = 28.4% probability that a randomly selected package of grapes weighs more than a randomly selected package of honeydew slices.
A similar problem is given at https://brainly.com/question/24663213
the interval [2, 4] is divided into n equal subintervals of length delta x. What is delta x (in terms of k and n)
Answers
Each subinterval would have length ∆x = (4 - 2)/n = 2/n
expand and simplify
(y – 2) (+1) (y+3)
Answers
Answer:
y² + y - 6
Step-by-step explanation:
(y - 2)(+ 1)(y + 3) simplifies to
(y - 2)(y + 3)
Each term in the second factor is multiplied by each term in the first factor, that is
y(y + 3) - 2(y + 3) ← distribute parenthesis
= y² + 3y - 2y - 6 ← collect like terms
= y² + y - 6
Jett is 6 feet 2 inches tall. How tall is he in inches ?
Answers
Answer:
74in
Step-by-step explanation:
Jett is 74 inches tall, as of the given unit conversion condition.
What is simplification?The process in mathematics to operate and interpret the function to make the function or expression simple or more understandable is called simplifying and the process is called simplification.
here,
1 feet = 12 inches
So,
6 feet 2 inch = 6 feet + 2 inch
= 6 × 12 inch + 2 inch
= 72 + 2
= 74 inches
Thus, Jett is 74 inches tall, as of the given unit conversion condition.
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Solve the equation.
2x - 3 + 4x = 21
A)x = -12
B)x= -6
C)x= 4
D)x = 6
Answers
Answer:
C. X=4
Step-by-step explanation:
Both questions 7 and 8
Answers
9514 1404 393
Answer:
7. $10,459.28
8. $30,060.93
Step-by-step explanation:
Your table 12-2 will tell you the present-value multiplier of the annual payment for a 10-year annuity due will be ...
7%: 7.515232
11%: 6.537048
__
7. The 11% table value will be used with a payment of $1600 to find the present value:
6.537048 × $1600 = $10,459.28 . . . present value of the annuity due
__
8. The 7% table value will be used with a payment of $4000 to find the present value:
7.515232 × $4000 = $30,060.93 . . . present value of the annuity due
Jonas is conducting an experiment using a 10-sided die. He determines that the theoretical probability of rolling a 3 is StartFraction 1 over 10 EndFraction. He rolls the die 20 times. Four of those rolls result in a 3. Which adjustment can Jonas make to his experiment so the theoretical and experimental probabilities are likely to be closer?
A.He can decrease the sample space.
B.He can increase the sample space.
C.He can decrease the number of trials.
D.He can increase the number of trials.
Answers
Answer:
A. He can decrease the simple spacw
Answer:
D. He can increase the number of trials
Anyone know the answer to this plz
Answers
Answer:
Domain: -10 < x < 10
Range: -2 < y < 8
Step-by-step explanation:
Hope this helps!
Your deductible expenditures are $8236 for interest on a home mortgage, $3528 for contributions to charity, and $634 for state income taxes. Your filing status entitles you to a standard deduction of $12,200. Should you itemize your deductions rather than claiming the standard deduction? If so, what is the difference?
Answers
Answer:
yes 198
Step-by-step explanation:
(10 points!!!) AND I’LL GIVE YOU BRAINLIEST IF CORRECT
I ALREADY KNOW THE ANSWER I JUST WANT THE EXPLANATION!!
Janell deposits $2,000 and for 5 years leaves it in an account earning 3% annual interest, compounded quarterly. For 5 years, José saves and deposits $150 per quarter in an account earning 3% interest compounded quarterly. Who will have more money in the account after 5 years? How much more?
Use the table to answer:
Answers
Answer:
of which class is it ?
Step-by-step explanation:
???????.................
2) Subtract and simplify. 11 7\10 − 7 3\10 =
Answers
Answer:
4 2/5
Step-by-step explanation:
11 7/10
- 7 3/10
----------------
4 4/10
4 4/10 = 4 2/5
Find the equation of the line through (2,1) which is parallel to the line y=−7x−1.
Give your answer in the form y=mx+b
Answers
Answer:
y=-7x+15
Step-by-step explanation:
PLEASE HELP WITH THIS ONE QUESTION
Answers
Answer:
g(x) = x(x-2)^2(x-3) -3
Step-by-step explanation:
the translation from f(x) to g(x) is right 1 down 3.
vertical translations are easier since you just add the amount to everything. so we have f(x) - 3 = (x-1)^2(x-2)(x+1) -3.
for the horizontal translation, we make every x into x-1, so now we have (x-1-1)^2 (x-1-2) (x-1+1) - 3 or (x-2)^2(x-3)x -3
looking at the answers it is g(x) = x(x-2)^2(x-3) -3
Line l is a reflection in the x-axis of line k. Write an equation that represents line k.
Answers
Answer:
(-4,3)
Step-by-step explanation:
nejsjsjssjsususheheueueyeehejebebe
Answer: y = (5/3)x + -1
Step-by-step explanation:
The slope is -5/3, so since its a reflection in the x - axis, the new slope would be the opposite, 5/3. Now for the +1, you just have to find the y intercept by plotting the dots at the opposite version of the y number that is already there. For example because the point (0,1) has 1 as its y number, you make it into -1, and for example if you have the point (3,-4) since -4 is the y number you change it to 4.
Cuál es la altura (h) del velero
Answers
Utilizando propiedades de triángulos rectángulos, veremos que la altura h es igual a 4.28m
Lo primero que debemos notar es que tenemos un triangulo rectángulo. En el podemos ver un ángulo de 55°.
El cateto adyacente tiene una longitud de 3m, y queremos obtener la longitud del cateto opuesto.
Podemos usar la relación trigonométrica:
Tan(θ) = (cateto opuesto)/(cateto adyacente)
Reemplazando los valores que conocemos, obtendremos:
Tan(55°) = h/3m
Tan(55°)*3m = h = 4.28m
La altura h del velero es 4.28m
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Pls help me with these Worksheets :(
My brain cells aren't working lol
(AGAIN IF YOU DON'T KNOW THE ANSWERS PLS JUST IGNORE THIS!)
Answers
Answer:
I'm sorry. It's messy ik.
For number 5 that I haven't done, I don't get the answer :((( so...
But basically, the speed is found by multiplying the distance and time. The distance is the same either you go upstream or downstream. Hope it help!
Answer:
Step-by-step explanation:
I'll do #5 second page
let (v) be rowing velocity in still water
let (s) be the stream velocity
d = vt
going downstream
24 = (v + s)4
24 = 4v + 4s
4s = 24 - 4v
s = 6 - v
going upstream
24 = (v - s)6
24 = 6v - 6s
24 = 6v - 6(6 - v)
24 = 6v - 36 + 6v
60 = 12v
v = 5 km/hr
s = 6 - 5 = 1 km/hr
Assignments
In a lottery, the top cash prize was $633 million, going to three lucky winners. Players pick four different numbers from 1 to 52 and one number from 1 to 41
A player wins a minimum award of $400 by correctly matching two numbers drawn from the white balls (1 through 52) and matching the number on the gold ball (1
through 41). What is the probability of winning the minimum award?
Study Plan
Gradebook
The probability of winning the minimum award is
(Type an integer or a simplified fraction
Answers
The probability of winning the minimum award is very small, approximately 1 in 185 million.
To calculate the probability of winning the minimum award, we need to determine the number of possible outcomes and the number of favorable outcomes.
To win the minimum award, the player needs to match two of the white ball numbers and the gold ball number.
There are (4 choose 2) ways to choose two of the four white ball numbers, and there is only one way to choose the gold ball number. Therefore, the number of favorable outcomes is (4 choose 2) × 1.
So, the probability of winning the minimum award is:
(favorable outcomes) / (total outcomes)
= [(4 choose 2) × 1] / [(52 choose 4) × 41]
= (6 × 1) / (26,827,440 × 41)
= 6 / 1,100,701,040
≈ 0.0000000054 or 5.4 × 10⁻⁹
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Are the two triangles congruent?
Choose 1 answer:
(Choice A)
A-Yes
B-No
C-There is not enough information to say.
Answers
Choose the missing step in the given solution to the
inequality -X - 10 > 14 + 2x.
_X
- 10 > 14 + 2x
-3X - 10 > 14
x<-8
0 -3x > 24
0 -3x > 4
0-3x>.
- 4
0 -3x < 24
Answers
Answer:
Step-by-step explanation:
after how many years will £6,000.00 yield a simple interest of £900.00 at 3%
Answers
Answer:
add 1 Century to divide £6 000 000
Answer:
the answer to your question is 105 I think sorry if it's not
solve for x, x-c=r+d/y
Answers
Answer:
D
Step-by-step explanation:
x - c = (r + d)/y for x
x = (r +d)/y + c common denominator : (c/1) (y/1) = yc
x = (r + d)/y + yc
x = (yc + r + d)/ y
What is the rectangular form of theta = 3pi/4?
Please answer this question if you 100% know this answer.
a. x - y = 0
b. x - y = 1
c. x + y = 0
d. x + y = 1
The answer was not a.
Answers
Answer:
c. x + y = 0
Step-by-step explanation:
The terminal ray of the angle θ = 3π/4 extends to the upper left through the 2nd quadrant with a slope of -1. It lies on the line ...
y = -x
x + y = 0 . . . . . . add x to get this standard form equation
Last year, wind turbines along a hilly ridge had an average output of 390 kilowatt hours per
year. The turbines were upgraded, and now their average annual output is 30% more. What
is the new average yearly output?
kilowatt hours
Submit
Answers
Answer:
507 KW/hStep-by-step explanation:
Initial output:
390 KW/hUpgraded output:
30% moreFind the upgraded output in number:
390 + 30% of 390 =390 + 390*30/100 =390*1.3 =507Average output=390KW
Updated percentage=30%
Updated output:-
[tex]\\ \sf\longmapsto 30\%\:of\:390[/tex]
[tex]\\ \sf\longmapsto 0.3(390)[/tex]
[tex]\\ \sf\longmapsto 117[/tex]
New output=390+117=507KW
1. What kind of sequence is this? 44, 57, 70, 83, .. arithmetic ,geometric,
both , neither
Answers
Answer:
arithmetic
Step-by-step explanation:
arithmetic
There is a common difference of 13 between each term.
can someone PLEASE help me with this!? I’ve been trying to find the answer but I just couldn’t find it. I’m behind in math and this was due four days ago!!
Answers
Answer:
{-2}
Step-by-step explanation:
Answer:
B)-2
Step-by-step explanation:
In functions, X is your input. Y is the output unless specifically stated otherwise :P
Brainliest? <3
i need help with this please
Answers
The bag has 99 buttons. Draw more buttons so there are 105 buttons in all. Write the numbers as you count.
Answers
Answer:
100 101 102 103 104 105
Step-by-step explanation:
im kinda confused
1. Find the coordinates of all points where the lines
x + y = 8, y = 5, and x = 1 intersect.
Answers
Answer:
(3)1. Find the coordinates of all points where the lines
x + y = 8, y = 5, and x = 1 intersect.
Step-by-step explanation:
this answer
The coordinates of all points where the lines x + y = 8, y = 5, and x = 1 intersect are (0, 5), (1, 0), (3, 5) and (1, 7).
Given that;
The equation of lines is,
x + y = 8
y = 5
x = 1
Now all the coordinates of all points where the lines x + y = 8, y = 5, and x = 1 intersect are find as,
x + y = 8
Put y = 5;
x + 5 = 8
x = 8 - 5
x = 3
Put x = 1;
1 + y = 8
y = 8 - 1
y = 7
Therefore, the points are (0, 5), (1, 0), (3, 5) and (1, 7).
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last one i’m almost done.
Answers
Answer:
AFC
Step-by-step explanation:
You can tell by the angles
Which number(s) is/are greater than 125%?
-1.26
0.125
12/5
8/6
Pick 2
Answers
12/5 12/5. 12/5 hdhfhd y hh