B. 350 kg m/s. A skier of 70kg at 5m/s down a slope will have a momentum of 350kg m/s.
The linear momentum or momentum is represented by the letter p and is defined as the product of the mass of a body by its velocity, that is:
p = m · v
Therefore, when a body is in motion it has a non-zero moment. If it is at rest, its moment is zero. In the International System, it is measured in Kg · m / s.
A 70 kg skier moving at 5m/s down a slope will have a momentum:
p = (70kg)(5m/s) = 350kg m/s