Please Help with number 3. Please show the work on how to get it also. Easy Points.

Mary works for a company that ships packages and must measure the size of each box that needs to be shipped. mary measures a box and finds the length is 7 inches, the width is 14 inches, and the height is 15 inches. what is the volume of the box? [type your answer as a number.]

The sum of two numbers is 86, and their difference is 20. find the two numbers

The base of a triangle exceeds the height by 7 centimeters. if the area is 400 square centimeters, find the length of the base and the height of the triangle.