[W]? 4. A car changes its position from 52 km [W] to 139 km (E).
What is the car's displacement?

87 km I think

The heat absorbed from the heating of water can be calculated by the product of the mass of the sample, specific heat and the difference in temperature. From the given data, we can simply calculate the mass of the sample as follows:

H = mC(T2-T1)
2500 = m(4.186)(60-20)
m = 14.93 g