Can someone explain this to me? i really don't understand how to do it. i need asap

THIS IS ONLY FOR THE RECTANGLE SRY I COUDLNT DO THE

0.25 ft^3

A rectangular tank is a generalized form of a cube, where the sides can have varied lengths. It is bounded by six faces, three of which meet at its vertices, and all of which are perpendicular to their respective adjacent faces. The equation for calculating the volume of a rectangle is shown below:

volume= length × width × height

EX: Darby likes cake. She goes to the gym for 4 hours a day, every day, to compensate for her love of cake. She plans to hike the Kalalau Trail in Kauai and though extremely fit, Darby worries about her ability to complete the trail due to her lack of cake. She decides to pack only the essentials and wants to stuff her perfectly rectangular pack of length, width, and height 4 ft, 3 ft and 2 ft respectively, with cake. The exact volume of cake she can fit into her pack is calculated below:

volume = 2 × 3 × 4 = 24 ft3