Explanation pls? step by step i get confused on these questions! thank you!

How many doughnuts are equal to 20 cookies.? 3 apples = 5 bananas6 cookies = 7 apples2 doughnuts = 1 banana

Now, martin can reasonably guess that the standard deviation for the entire population of people at the mall during the time of the survey is $1.50. what is the 95% confidence interval about the sample mean? interpret what this means in the context of the situation where 95 people were surveyed and the sample mean is $8. use the information in this resource to construct the confidence interval.

Twice the sum of a number and 2 is equal to three times the difference of the number and 8. find the number.