[填空题]
A 70-cm-diameter whe4 qk c3q5.aj+kj.-zpr c trdj,el accelerates uniformly about ie. f dwoeb3 iy/k1e:d:ts center from 130 rpm to 280 rpm in 4.0 s. Determinde k:/b1 od:w.i3f yeee (a) its angular acceleration,$\approx$ $rad/s^2$(Round to one decimal places) (b) the radial and tangential components of the linear acceleration of a point on the edge of the wheel 2.0 s after it has started accelerating. $a_R$ $m/s^2$ $a_{tan}$ $m/s^2$