#### Answer

(a) $F = 1.0\times 10^5~N$
(b) $F = 2.25\times 10^4~lb$
(c) This huge force does not crush the desk because air pressure is not just a downward force. There is no pressure difference between the top of the desk, the bottom of the desk, the sides of the desk, or the air within the desk.

#### Work Step by Step

(a) We can find the downward force exerted on the desktop:
$F = P~A = (1.0\times 10^5~N/m^2)(1.0~m^2) = 1.0\times 10^5~N$
(b) We can convert this force to units of pounds:
$F = (1.0\times 10^5~N) \times \frac{0.225~lb}{1~N} = 2.25\times 10^4~lb$
(c) This huge force does not crush the desk because air pressure is not just a downward force. There is no pressure difference between the top of the desk, the bottom of the desk, the sides of the desk, or the air within the desk.