A scuba diver stays underwater for 30 minutes. How is this possible when the air tank is so small?

Here's the

Explanation:

An average open-water certified diver using a standard aluminium 80-cubic-foot tank on a 40-foot dive will be able to stay down for about 45 to 60 minutes before surfacing with a safe reserve of air still in the tank.

Three Factors That Determine How Long a Diver's Air Will Last:

1. Tank Volume

2. Depth

3. Air Consumption Rate

two charges are fixed in place on the x-axis as shown. the charge at x = 0 is negative and has magnitude q = 2 μcoulombs (1 μcoulomb = 10-6 coulombs). the charge at x = d, (d = +12 cm), is positive and has magnitude q = 4 μcoulombs. find a point x = xo along the x-axis at which the electric field is zero.