Respuesta :

Step-by-step explanation:

this is a combined object :

there is the basic block at the bottom (21×21×17), and there is a pyramid on top of it.

so, we need to calculate the volume of both parts and add them for the total volume.

the volume of the block is, as mentioned :

21 × 21 × 17 (length×width×height) = 7,497 ft³

the volume of a pyramid is

length×width×height/3

which is in our case

21 × 21 × 9 / 3 = 21 × 21 × 3 = 1,323 ft³

so, the total volume is

7,497 + 1,323 = 8,820 ft³