[填空题]
Express the following anglbho6jm3wofgw+l 9. . bes in radians: (a) 30 o-tm 4kd)t- nrev9pd a csn5+(rno8h)$^{\circ} $, (b) 57 $^{\circ} $, (c) 90 $^{\circ} $, (d) 360 $^{\circ} $, and (e) 420 $^{\circ} $. Give as numerical values and as fractions of $\pi$.(Round to two decimal places) (a) $rad$ (b) $rad$ (c) $rad$ (d) $rad$ (e) $rad$