68) How many square of size 100 mm x 100 mm can be cut from a sheet of size 500 mm x 1000 mm?

69) The cutting speed of a tool when turning 10 mm diameter rod with 100 rpm is _____ m/minute

70) A ladder is leaned against a vertical wall. The angle between the ladder and the floor is 60 degree. What is the angle between ladder and wall?

71) A sum of Rs. 5000 yields an interest of Rs. 500 in a year. What is the rate of interest?