Answer:
a) sample size is 40
Step-by-step explanation:
(a)
minutes
Margin of error, E is 75 seconds E=75/60= 1.25 minutes.
The level of significance 
for 95% level of significance
For 95% confidence interval 
from standard deviation table
Sample size required, n
Rounding off, n=40
Sample size =40
Keywords:
95% confidence, sample size, Wall Street Journal
To solve the problem w must know about the Associative property.
<h2>Associative property</h2>
The associative property states that the addition of the sum of two numbers (a,b) and a third number(c) is equal to the addition of the sun of the last two numbers(b, c) and the first number(a).
The property that will allow Carmen to do this without changing the value of the expression is the Associative property.
<h2>Explanation</h2>
Given to us
<h3>Associative property.</h3>
Now, using Associative property,
(6.21 + 0.93 ) + 0.07
= 6.21 + (0.93 + 0.07)
=6.21 + (0.93 + 0.07)
Hence, the property that will allow Carmen to do this without changing the value of the expression is the Associative property.
Learn more about Associative property:
brainly.com/question/1680548
Answer:
9.8
Step-by-step explanation:
7.5+2.3y-y
Subtract y
7.5+2.3
Then Add
9.8
Answer:
<h2>Michael needs to save $63.40, approximately.</h2>
Step-by-step explanation:
The given expression is
Where 
is months.
We need to solve for the variable.
Therefore, Michael needs to save $63.40, approximately.
