Questions

The main difference lies in the motive of the two parties. The main motive of the hedger is to hedge(minimize) the risk from the occurence of some events. 

The motive of the speculator is to gamble in the market in order to make the profit by buying/selling the derivative products.

Air contains water in a gaseous form called water vapour.

Nuclear Power Plant uses a Non Renewable Energy Source.

Non-renewable energy is that source of energy which can not be used again and again. This sort of energy is sustainable to exhaustion.

Non renewable energy is that form of energy which is subject to deletion. This type of energy is of many uses to us. It can be used to produce electricity, heating, cooking, transportation and manufacturing. 85% of the energy used in the industrial processes is form the non-renewable type of energy.

Magnetism in materials is due to circular motion of electrons.

Secondary storage therefore needed because it is non-volatile, meaning it retains its contents without the need for a power supply. It also has the large storage capacity needed to store the operating system and all the programs and files needed by a modern computer system.

The required number is SEVEN.

If you remove  S, it becomes EVEN.

Assessing opportunity cost involves making choices and dealing with consequences.