1. As a certain sound wave travels through a kind of gas (density 1.20 kg/m3), it produces pressure variations (above and below certain pressure) given by AP = 2.54 sin [TEX/2 + 200m+3n/4)], with all quantities in SI units. What is the displacement amplitude of the wave? (a) 4.21x10-6 m (b) 1.68x10'5 m (c) 1.01 x 10'5 m (d) 8.42x10'6 m (e) 9.82x10'6 n1