From an aeroplane just over a river, trees on the opposite bank of the river are found to be 60° and 30° respectively. If the breadth of the river is 400 m, then the height of the airplane above the river at an instant is (assume √3 = 1.732)
Three successive discounts of 40%, 25% and 20%, respectively, on the marked price of a chair, are equal to a single discount of Rs.960. The marked price (in Rs) of the chair is: