A cube of edge 15cm is immersed completely in a rectangular vessel containing water. If the dimensions of the base of vessel are 20cm * 15cm , find the rise in water level?
Select the correct option:  A) 6 cm  B) 8.25 cm  C) 11.25 cm  D) 15.12 cm  E) 20.62 cm

Rationale: "increase in volume = volume of the cube = 15 * 15 * 15 cm ^ 3 rise in water level = volume / area = 15 * 15 * 15 / 20 * 15 = 11.25 cm answer is c"
Answer: C