The force required to lift the load is its weight.
Weight = (mass) x (gravity)
so Work = (mass) x (gravity) x (distance)
Now Power = (work) / (time)
so Power = (mass) x (gravity) x (distance) / (time)
= (700kg) x (9.8 m/s²) x (2 m) / (0.4 sec)
= ( 700 x 9.8 x 2) / (0.4) (kg-m²/sec²) / (sec)
= ( 34,300 ) (joule) / (sec)
= 34,300 watts .
This is one of those exercises where the math and the physics are air-tight and bullet-proof but the answer is absurd.
34,300 watts is about 46 horsepower. I don't care how many Wheaties Power Lifter Paul had for breakfast today, he is NOT snatching a barbell that weighs 1,543 pounds (0.77 ton !) to the height of the top of his head in less than 1/2 second !
