A constant head permeameter contains three different soils, 1, 2, and 3, where 1 is on top of 2, and 2 is on top of 3. Their hydraulic conductivities are: k soil 1 = 9 cm/s, k soil 2= 6*10^2 cm/s and k soil 3= 8*10^(-3). The four piezometer (A,B,C,D) tips are spaced at 100 mm intervals, where tip A is in soil 1, tip D is in soil 3, tip B is on the interface of 1 and 2, and tip C is on the interface of soils 2 and 3. The total heads given by piezometers A and D are 98.9 cm and 3.6 cm, respectively. What are the total heads given by piezometers B and C?