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
The missing length is 10
Step-by-step explanation:
Represent the missing length with x
The sides of the given shape are directly proportional.
Mathematically:
(15 + x) to (12 + 8) and x to 7
Represent as a ratio:


Convert to fraction

Cross Multiply:


Collect Like Terms


Solve for x


<em>The length of the missing side is 10</em>
Answer:
The answer is 2/5 or 5.25
Step-by-step explanation:
5 sections so out of 5 and it said A or B so it is 2/5
<span>Theorem:
A tangent to a circle forms a right angle with the circle's radius, at the point of contact of the tangent.</span>
Reliable taxis : for 30 miles
C = 1.5x....x = 30
C = 1.5(30)
C = 45
speedy taxis : for 30 miles
C = 1.1x + 11.5....x = 30
C = 1.1(30) + 11.5
C = 33 + 11.5
C = 44.5
city taxis : for 30 miles
C = 1.25x + 8...x = 30
C = 1.25(30) + 8
C = 37.5 + 8
C = 45.5
the cheapest company is : speedy taxis