Final answer:
The constant speed at which the cable must be drawn in by the motor to hoist the load 9 m in 1.5 s is 6 m/s.
Step-by-step explanation:
To hoist the load 9 m in 1.5 s, we can use the equation: speed = distance / time. The constant speed at which the cable must be drawn in by the motor can be calculated as:
Speed = 9 m / 1.5 s = 6 m/s
Therefore, the cable must be drawn in at a constant speed of 6 m/s in order to hoist the load 9 m in 1.5 s.