Marion Ryan, age 10, of Rowayton, Connecticut, for her question:

How many pounds of salt are in the ocean?

Get a pencil and paper, because you will have to do some of the figuring for yourself. What's more, Andy does not promise that the final answer will be 100 per cent perfect    right down to the last sixteen ounces. Scientists can only estimate the amount of salty chemicals dissolved in the great worldwide ocean. And they admit that their best estimates may be wrong    perhaps a few million tons wrong.

They figure that the ocean holds 50 quadrillion tons of dissolved salty chemicals. This large number is 50 with a tail of 15 zeros. There are, as you know, 2,000 pounds in each and every salty ton. So get busy with your pencil and multiply 50 quadrillion by 2,000. The final answer will tell you how many pounds of salt are dissolved in the ocean    but don't expect the answer to be perfectly accurate.