10 Points, I need the answer plus an explanation on how to get the answer

Which of these figures must be a rectangle?

Vikram is studying the square pyramid below. on st to find the surface area of the pyramid, in square inches, vikram wrote (33.2) (34 ikram wrote (33.2)(34.2)+43(34.2)(284) what error did vikram make? o he used the same expression for the area of all four lateral faces. he used the wrong expression to represent the area of the base of the pyramid. o he used the wrong value as the height when he found the area of the lateral faces. he used an expression for surface area that only finds the total area of three faces.

As a salesperson you get $23/ day and $3.60/each sale you make. if you want to make at least $84. in one day, how many sales would need to make? a 15b 16c 17d 18