Answer: 
Step-by-step explanation:
As per given , we have
n = 11

Since population standard deviation is missing, so we use t-test.
Critical t-value for 99% confidence :
[using two-tailed t-value table]
Confidence interval :

Hence, 99% confidence interval for the mean amount of time that students spend in the shower each day.= 
Answer:
10√5 - 5√2
or
5(2√5 - √2)
Step-by-step explanation:
Given:
2√5(5 - 5√5)
Required:
Multiply and simplify
Solution:
2√5(5 - 5√5)
Apply distributive property by multiplying each term in the bracket by 2√5
2√5*5 - 2√5*5√5
2*5√5 - 2*5√5*√5
10√5 - 10√25
10√5 - 10*5
10√5 - 50
10√5 - (25*2)
10√5 - 5√2
Or
5(2√5 - √2)
27 + x is the simplified expression.
Answer:
The amount that the landscaper mowed in one hour would be 1.5 yards.
Step-by-step explanation: