A swimmer can swim downstream at 13 km/h and upstream at 7 km/h. Find the speed of swimmer in still water.A6 km/hB20 km/hC10 km/hD8 km/hAnswer: C. 10 km/hRead Explanation:Let speed of swimmer in still water is S and speed of current is C S + C = 13 S - C = 7 S=[13+7]/2 =10Open explanation in App