[填空题]
Calculate (a) the rms spee+4v eb 3n*r .u4wglphn ou/ 4p7tdgi:od of an oxy4 6:05yisjf l+jen)uecn35j x e2k axsgen molecule at 0 $^{\circ} $ C m/s
(b) determine how many times per second it would move back and forth across a 7.0-m-long room on the average, assuming it made very few collisions with other molecules. round trips per sec