89) The thickness of a light gauge sheet steel can be best checked with a

90) The ratio of number of boys and girls in a school of 720 students is 7:5. How many more girls should be admitted to make the ratio 1:1?

91) Which ofthe following can be used as an Inverter?

92) BCG vaccine is used against

93) A boat takes thrice as much time to sail in the upstream of a river as it would have taken to sail in the downstream. If the speed of the water is 5 kmph, then the speed of boat in still water is