The diagonals of a trapezium are at right angles,and the slant sides if produced,form an equilateral triangle with the greater of the two parallel sides.If the area of the trapezium is 16 sq.cm,then the distance between parallel sides is

The sides of a triangle are 25cm,39cm and 56cm.The perpendicular from the opposite vertex on the side of 56cm is

A rectangular block of wood having dimensions 3m*2m*1.75m has to be panted in all its faces.The layer of paint must be 0.1mm thick.Paint comes in cubical boxes having their edges equal to 10cm.The minimum number of boxes of paint to be purchased is

The last digit in the expansion of 17^256

The total surface area of a right circular cone of height 24cm with a hemisphere of radius 7cm upon its base is π

Water flows through cylindrical pipe of internal diameter 7cm at the rate of 5m/s.The time,in minutes,the pipe would take to fill an empty rectangular tank 4m*3m*3.1m is