Pick up the correct statement from the following:

Age of a tree may be ascertained by

For slaking of 10 kg of CaO, the theoretical amount of water is

Vanadium steel is generally used for

If the furnace is provided with insufficient fuel at low temperatures, the type of pig iron produced, is called

To retard the initial setting time of cement, the compound responsible, is

Which of the following is the purest form of iron?

After storage, the strength of cement

For obtaining vinyl chloride acetate, the method used, is