Two waves are traveling in opposite directions on the same string. The displacements caused by the individiual waves are given by y1= (25.0 mm)sin(8.80rrt - 1.86m) and y2=(34.0 mm)sin(3.30rrt + 0.328nx). Note that the phase angles (8.80m - 1.86m) and (3.30m + 0.3281'rx) are in radians, t is in seconds, and x is in meters. At t = 4.00 s,what is the net displacement (in mm) of the string at (a)x = 2.20 m and (b) x = 2.92 m? Be sure to include the algebraic sign (+ or -) with your answers. (a) Number n Units (b) Number a Units {b (b A speaker has a diameter of 0.348 m. (a) Assuming that the speed of sound is 343 m/s, find the diffraction angle 0 for a 2.29-kHz tone. (b) What speaker diameter D should be used to generate a 6.32-kHz tone whose diffraction angle is as wide as that for the 2.29-kHz tone in part (a)? (a) Number 31.65 Units deg (b) Number Units m