[填空题]
The blades in a blender rotate at a rxsw)/k 8ukb o;alzsaw:xg 5d: h52/es ste of 6500 rpm. When the motor is turned off during operation, the blades slow to rest in 3.0 s. What is the angular acxl wz g/s5: :5she2sdaceleration as the blades slow down? $rad/s^2$