A80 kg firefighter climbs of stairs 6 meter high in ten seconds

4704 Joules

We are given;

Assuming we are required to calculate the work done by the firefighter;

We are given mass as 80 kg

But, 9.8 N = 1kg

Therefore,

Force = 80 kg × 9.8 N/kg

          = 784 N

Therefore,

Work done = 784 N × 6 m

                   = 4704 Joules

depends on what you mean by "group." for order, it would be coleoptera (beetles). for class, it would be insecta (insects). for phylum, it would be the arthropoda (animals with jointed exoskeletons).

explanation:

the chart show the masses and velocities of two colliding objects that stick together after a collision.

according to the law of conservation of momentum, the momentum of the object after the collision is  

answer

1,500

kg • m/s.