She would be able to tip 7 waiter if she has enough money left over to tip the 7 waiters.
hope this helped have a nice day:)
Answer:
Here we will use the relationships:



And a number:

is between 0 and 1 if a is positive and larger than 1, and n is negative.
if a is positive and 0 < a < 1, then we need to have n positive such that:
0 < a^n < 1
A) 
This is between zero and 1,
B) 
This is greater than 1, because the exponent is positive.
C) 
Because a is smaller than 1, and the exponent is positive, then the expression is between 0 and 1.
D) 
The exponent is negative (and pair) then the expression is between 0 and 1.
Remember that when the exponent is pair, we always have that:
(-N)^m = (N)^m
So (-7)^-2 = 7^-2
The equation for standard deviation is finding the mean of the numbers, subtracting each of the initial numbers by the mean, squaring each of the results, finding the mean of these results added together, then finding out the square root of the results added together.
The mean of 175 and 165 is 170, subtract 175 and 165 by 170, and you get 5 and -5 respectively. Then, square the results and you get 25 and 25.
Add the two numbers together (25 & 25) then find the square root of it, which is <span>7.07106781187, simplified to 7.07.</span>
Well, for 4 I believe you must divide 2/4 by 100 to make it a decimal, then divide the decimal by the 5. :) Hopefully that is correct!