試題詳解

2. All edges of a cube are expanding at a rate of 4 centimeters per second. How fast is the volume changing when each edge is 5 centimeters?
(A) 100 cm³/sec
(B) 300 cm³/sec
(C) 200 cm³/sec
(D) 240 cm³/sec
(E) 80 cm³/sec