2. (10 p) A barrel shown in the figure is full of water. The water temperature at different depths ( h ) vary according to the function ln(h+1) T h =45 C- 1 from surface to bottom (in cm) i.e. h = 0 cm means depth of 0 cm, at the surface. The barrel is 180 cm high and the cross-section circle radius at surface and bottom is 45 cm. The sides of the barrel bend in a form of parabola and the radius in the middle ofthe barrel is 52 cm. How much heat / energy is released as the temperature of the water in the tank decreases to 5 C ? The energy released is calculated in the same way as the energy required to heat object, i.e. Q = chT, in which 0 m is the mass of the water that is being cooled k 0 c = 4,19 Elm is the water heat capacity 0 Mass is product of density and volume: m = pV 0 Water density is p = 1000%