Why does a beekeeper keep beehives in crop fields during the flowering periods? State any two advantages.

Why are beehives kept in crop field during flowering period? Name any two crop fields where this is practiced.

Honey collection improves when beehives are kept in crop fields during flowering periods?Explain.

For any substance, Why does the temperature remain constant during the change of state?

Explain why the two field lines never cross each other at any point?

These questions consist of two statements each,printed as Assertion and Reason.While answering these questions you are required to chose any one of the following four responses. If both Assertion and Reason are true and Reason in correct explanation of Assertion. If both assertion and Reason are true but reason is not correct explanation of Assertion. If Assertion is true but Reason is false. If both Assertion and Reason are false. Assertion:A woman does not conceive during the lactation period. Reason:the hormone prolactin stimulates(a)the growth of milk glands during pregnancy and (b) secretion of milk in a postpartum woman.