Answer:
The nutritionist have enough evidence to reject the writer’s claim .
Explanation:
Claim : The average number of calories in a serving of popcorn is different from 75
Null hypothesis :

Alternate hypothesis :

n = 20
Sample standard deviation s = 7

Since n < 30 and population standard deviation is not given .
So, we will use t - test .
Formula :

Substitute the values


So, t calculated = 1.9166
Degree of freedom = n-1 = 20-1 = 19
Refer the t table
So,

Since t critical > t calculated
So, we are fail to reject the null hypothesis .
So, the nutritionist do not have enough evidence to reject the writer’s claim .