Answer:
The return of blood to the heart is assisted by the action of the skeletal- muscle pump. As muscles move, they squeeze the veins running through them. Veins contain a series of one-way valves, and they are squeezed, blood is pushed through the valves, which then close to prevent backflow.
<span>Ferrite Magnets (</span><span>ferromagnetic or ferrimagnetic) </span>are the kinds of magnets in a fridge magnet. <span>A refrigerator magnet is made of </span>powdered ferrite<span> (iron rust) and a liquid binding agent of </span>plastic<span> or rubber. The two are heated, mixed together, and poured into a sheet mold which is then exposed to a strong magnetic field.</span>
I’m not sure but I think the answer is B or D