Kiran swims in a 90 m long pool. He covers 360 m in two minutes by swimming from one end to the other and back 0 along the same straight path, twice. Find the average speed of Kiran.
The cost of levelling a circular field at 50 Paise per square metre is Rs 7700. The cost (in Rs) of putting up a fence all round it at Rs 1.20 per meter is ( Use π = 22/7)