51: Saka era commenced from:
(a) 78 AD
(b) 120 AD
(c) 1000 AD
(d) 1953 AD
52: The places Alwaye, Koyna and Korba have:
(a) Thermal Stations
(b) Oil Refineries
(c) Hydro Stations
(d) Aluminium Industries
53: The surface area of a cube is 216 sq.m. What is its volume ?
(a) 100 cu m
(b) 216 cu m
(c) 480 cu m
(d) 512 cu m
54: A table has three drawers. It is known that one of the drawers contains two silver coins, another contains two gold coins and the third one contains a silver coin and a gold coin. One of the drawers is opened at random and a coin is drawn. It is found to be a silver coin. What is the probability that the other coin in the drawer is a gold coin ?
(a) 0.25
(b) 1.00
(c) 0.50
(d) 0.60
55: Which of the following statements is true?
(a) Both salinity and density of sea increase with depth
(b) Both salinity and density of sea decrease with depth
(c) Salinity increases but density of sea decreases with depth
(d) Salinity decreases but density of sea increases with depth