28) The material with highest thermal diffusivity is

29) The energy used by a 1.5kW heater in 5 minutes is:

30) The equivalent resistance when a resistance of (1/6) Ohm. is connected in parallel with a (1/4) Ohm resistance is

31) Age of father is 10 less than 3 times his son's age. Eleven years after, age of father will be twice that of son's age. Then, the age of father is

32) The temperature at which ammonia changes from liquid state to gaseous state is (at atmospheric condition)