When the doctors measuring body pressure it is advisable to lie on a table. Why?

Sleeping pills are recommended by doctors' to the patients suffering from sleeplessness but it is not advisable to take its doses without consultation with the doctor. Why?

When water is frozen in glass bottles, it is advised not to fill the bottles completely. Explain the reason.

Mr. Raju has determined the molecular masses of different solutes in different solvents by osmotic pressure measurements and present them in the following table. Please help him to complete the table .

The vapour pressure of a liquid is a constant at constant temperature? Why?