Rafi said "flour from rice/wheat is a man made change". He wants to make a list of examples of this kind of changes. Help him expand his list.

Ravi wants to buy a bicycle. He goes to the market and finds that the bicycle of his choice costs Rs. 2,400. He has only Rs. 1,400 with him. To help, the shopkeeper offers to help him. He says that he can make a down payment of Rs. 1400 and pay the rest in monthly instalments of Rs. 550 each. Ravi can either take the shopkeepers offer or go to a bank and take a loan at 12% per annum simple interest. From these two opportunities which is the best one to Ravi. Help him.

Ravi's father wants to cultivate potato in his field . He wants to clarify some doubts with the agriculturals officer. Prepare a list of doubts in form of questions for him .