A metallic sheet is of rectangular shape with dimensions 40m x 30 m. From each of its corners, a square is cut off so as to make an open box. If the length of the square is 8 m, the volume of the box (in m cube) is:  Choose the most appropriate option:	A) 3220 m cube	B) 4140 m cube	C) 2688 m cube	D) 4000 m cube	E) none of these

Rationale: explanation : l = ( 40 - 16 ) m = 24 m , [ because 8 + 8 = 16 ] b = ( 30 - 16 ) m = 14 m , h = 8 m . volume of the box = ( 24 x 14 x 8 ) m cube = 2688 m cube . option c
Answer: C