Answer:
Average power output of athlete = 11025 Watts
Step-by-step explanation:
Work done is defined as the product of force applied and the displacement perpendicular to the force.
Work =

Power is defined as work done per unit time.
Power =

Here the person lifts 900 kg.
Height = 2.5 m
Time interval = 2 seconds
Force =

=

= 8820 N
Work done =

=

= 22050 J
Power =

= 11025 Watt