[填空题]
The blades in a blender rotate at a ratsvo;eh (q(xl4skg wx:ip ./i*e of 6500 rpm. When the motor is tuh7qvfu iu 08a 5sj2tt;rned otau; jht5s8 u2i7q0fvff during operation, the blades slow to rest in 3.0 s. What is the angular acceleration as the blades slow down? $rad/s^2$