Please answer quickly i need it

How do i get the answer for 2/3 * 10/3

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)?

Explain how you can use the associative property to evaluate (7x50)x4.