A company is to construct a parking bay whose area is 135 m2. It is to be covered with a concrete slab of uniform thickness of 0.15 m. To make the slab, cement, ballast and sand are to be mixed so that their masses are in the ratio 1:4:4. The mass of 1 m2 of dry slab is 2,500 kg. (a) Calculate (i) the volume of the slab (ii) the mass of the dry slab. (iii) the mass of cement to the used.(b) If one bag of cement is 50 kg, find the number of bags to be purchased.(c) If a lorry carries 7 tonnes of sand, calculate the number of lorries of sand to be purchased.