Answer:
The speed of the plank relative to the ice is:

Explanation:
Here we can use momentum conservation. Do not forget it is relative to the ice.
(1)
Where:
- m(g) is the mass of the girl
- m(p) is the mass of the plank
- v(g) is the speed of the girl
- v(p) is the speed of the plank
Now, as we have relative velocities, we have:
(2)
v(g/b) is the speed of the girl relative to the plank
Solving the system of equations (1) and (2)



I hope it helps you!
The correct response that will be used to describe this particular element would be the third option, since all of the other options are incorrect and apply to different elements in their groups. The element is a metal and will react with a non metal.
<span>A light-year measures the distance that light travels in 1 year.
Answer : B ) Distance
-Hope this helps.</span>
Answer: B
Explanation:
Biosphere breaks down rock of the geosphere (plant roots), but when it comes to soil, minerals of the geosphere feed the plants. Biosphere and atmosphere interact through animal and plant respiration of oxygen and carbon dioxide. Geosphere creates, destroys and keeps various biosphere places safe.