Find the total cost of wooden fencing around a circular garden of diameter 28 m, if 1m of fencing costs 300Rs.

Find the cost of fencing a circular garden of radius 21 m at Rs. 10 per metre.

Find the cost of fencing a semi-circular garden of radius 7 m at Rs. 10 per metre.

Find the cost of fencing a semi-circular garden of radius 7 m at Rs. 10 per metre.

Find the cost of fencing a semi-circular garden of radius 14 m at Rs. 10 per metre.

Find the cost of erecting of fence around a square field whose area is 9 hectares if fencing costs Rs 35 per metre.