Answer:
1% is available for drinking
Step-by-step explanation:
The vast majority of water, 97%, is in the oceans, where the salt levels make it non-potable. Of the remaining 3%, the word "available" narrows it down. Much of the remaining 3% is tied up in glaciers, ice caps, perma frost, or deep underground. If we subtract those out, since they are not easily "available, we're left with about 1% available for drinking.