A map is drawn to a scale of 1:75000.
(a) This scale can be expressed as | cm represents n km. Find 77.
(b) The distance between two towns on the map is 25 cm.
Find the actual distance, in kilometres, between the two towns.
(c) A lake has an actual area of 3.5 km.
Find the area, in square centimetres, of the lake on the map.
Give your answer correct to 3 significant figures.