(a) The decision of installing the solar water heater was correct this is due to
(i) Their system use solar energy which is a renewable source of energy and free
(ii)It will reduce our dependence on fossil fuel, improving on our energy security and reduce the country import bill for fuel.
(b) Two possible changes in the thinking of the family members because of the arguments given by Aditya are:
(i) We should conserve the non-renewable fuels for application for which renewable source of energy is not easily available.
(ii)Solar water heating is good investment and cost effective. It is one of the safe and efficient way to deliver hot water free of cost.