Determine if the following ratios form a proportion. Also, write the middle terms and extreme terms where the ratios form a proportion.(a) 25 cm : 1 m and Rs 40 : Rs 160(b)39 litres : 65 litres and 6 bottles : 10 bottles(c) 2 kg : 80 kg and 25 g : 625 g(d) 200 mL : 2.5 litre and Rs 4 : Rs 50