Can someone solve part a, b,c and d. Urgent plzzz

1mile equals approximately 1.6 kilometers. which best approximates the number of miles in 6 kilometers?

The weight of full–grown tomatoes at a farm is modeled by a normal distribution with a standard deviation of 18.4 grams. the 95 percent confidence interval for the mean weight of the tomatoes is calculated using a sample of 100 tomatoes. what is the margin of error (half the width of the confidence interval)?

Find the nonpermissible replacement for binthis expression.b2/5b +5