When 3 capacitors of capacities 2 mfd, 4 mfd and 4 mfd are connected in series, the effective capacity is

37) The color of the Freon-22 cylinder is

38) 2 atmosphere is equal to _____ PSIG.

39) The heat required to convert 2 kg of water at 100 degree C to 2 kg of steam is

40) "-40 degree fahrenheit in degree celsius"