Answer: 37
Step-by-step explanation:
Given : Significance level : 
Critical value : 
margin of error : E= 1 mile per gallon
Population standard deviation:
miles per gallon.
We know that when the population standard deviation is known then the formula to find the sample size is given by :

[Round to the next whole number.]
Hence, the required number of automobiles should be used in the test = 37
37 is 26%(rounded up to the nearest percent) of 144
D. 62 because if we separate the shape into two then one will be 5*4 and the other will be 7*6. Adding them up will equal the whole shape.