Answer:
1 cal / gm-C = 1000 cal /kgm-C specific heat of water
4.19 joules = 1 C
5.0E4 J / 4.19 J/C = 1.2E4 Calories = ΔQ
ΔQ = K M (T2 - T1) where K is the heat capacity
T2 = 12 + 1.2E4 / (1000 * 35)
T2 = 12 + 1.2E4 / 3.5 E4 = 12.34 C (only .34 deg C)