A chemical change may involve

Which of the following is/are true when milk changes into curd? 

(i) Its state is changed from liquid to semi-solid.

(ii) It changes colour.

(iii) It changes taste.

(iv) The change cannot be reversed.

Choose the correct option from below:

A man painted his main gate made up of iron, to 

(i) prevent it from rusting.

(ii) protect it from sun.

(iii) make it look beautiful.

(iv) make it dust free.

Which of the above statement(s) is/are correct?