In the first class lever the fulcrum is located between the effort and the resistance.In second class lever The second class of lever has the fulcrum at one end, the effort applied at the other end, and the resistance somewhere between those points. [ The third class of levers has the fulcrum at one end of the lever, and the weight or resistance to be overcome is at the other end, with the effort applied at some point between. ]
21: 4 and 15
22: 5
23:<span>1, 2, 3
I hope this helps</span>
C:your body can lose the ability to increase energy expenditure.
Answer:
you could possibly list gym trainers? or professional sports players? or track runners?
