Answer: 0.0775
Step-by-step explanation:
Given : Mean : 
Standard deviation : 
Sample size : 
Since its normal distribution , then the formula to calculate the z-score is given by :-

For x= 28.2 hours

For x= 30 hours

The P- value = 

Hence, the probabiliy that the average time spent stydying for the sampe was between 28.2 and 30 hours = 0.0775
The circumference of a circle of diameter 13 m is 13π m, about 40.82 m.
(40.82 m)/(2.5 m) = 16.328
16 may be the best approximation of the number of pieces Malia will need. 17 pieces will make a barrier that is longer (larger diameter) than is needed.
~Hello There!~

Rearrange for s

After 8 years, the new equation would be:

Cross multiply

Subtract 8

Substitute old equation

Solve to get m as 16.
s = 40.
Their current ages are 16 and 40 and the different is 24 years. Therefore, Caitlin is correct.
Hope This Helps You!
Good Luck :)
Have A Great Day ^_^
- Hannah ❤