[填空题]
The blades in a blender rotate at a rate of 6500 rp6 b4azweo y+5im. e6zi qr k0u6(cWhen the motor is turned off during operation, the blades slow to rest in 3.0 s. What is the angular acceleration as the blades slow down6uc0e qizr(k 6? $rad/s^2$