Many of the international problems we are now facing

You want to know the price of something so you say, ____ ?

Now that we have succeeded in isolating this drug and discovering its nature, our next problem is to plan its_______________ in the laboratory. Fill in the blank-

Choose the word which fits best in the text. He....to his men about the distance travelled each day. (Ans: a)

Choose the word that best completes the text. "People from all over the world are sent by their doctors to breathe the pure, ________air in this mountain region."