71) A sum of Rs. 7500 earns simple interest of Rs. 1500 in two years. What is the interest rate per annum?

72) When three unbiased coins are tossed, the probability of getting no head is

73) Which set does not represent the sides of a right angled triangle?

74) The area of an equilateral triangle is 8 square centimeter. Then the area of hexagon whose side is same as that of the equilateral triangle is