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:
662.433221
Step-by-step explanation:
907.07 × 1.09 × 0.67
Answer:
3
Step-by-step explanation:
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction
3^4 +9^2÷3^3-9^2
81+81÷27-81
81+3-81
3
Answer:
B
Step-by-step explanation:
The line is running only across coordinate points with an x coord of 2
There would be 14 female and 7 male, so the total number of students is 21.