Answer:
A parrot lifts a cracker off the ground to eat.
Step-by-step explanation:
Work is said to be done by a force only if the force causes displacement.
The formula to find Work is given as:
Where, 'W' is the work done, 'F' is the force acting and 'd' is the displacement of the object.
Displacement of an object is the net change in its position.
A body that is not moving has zero displacement.
Let us check each option now.
Choice 1:
A parrot lifts a cracker off the ground to eat.
Here, the lifts a cracker off the ground. So, the parrot applies some force on the cracker and the cracker's position has changed.
So, there is work done by the parrot as force causes a displacement.
Choice 2:
A weightlifter holds a 150 pound barbell for 3 minutes.
Here, no work is done as the force applied to hold the barbell is not producing any displacement.
Choice 3:
A waiter holds a tray of 15 glasses of water over his head while standing at the front of a restaurant.
Here, no work is done as the force applied to hold the glasses of water is not producing any displacement.
Choice 4:
A truck motor runs for 24 hours while the truck is parked.
Here, no work is done as the force applied to run the motor is not producing any displacement (truck is parked).
So, the correct choice is first choice.