The answer I had got was C x
Answer:
(c) 4M
Explanation:
The system is a loaded spring. The period of a loaded spring is given by

<em>m</em> is the mass and <em>k</em> is the spring constant.
It follows that, since <em>k</em> is constant,

where <em>C</em> represents a constant.


When the period is doubled,
.

Hence, the mass is replaced by 4M.
Answer: Blood primarily moves in the veins by the rhythmic movement of smooth muscle in the vessel wall and by the action of the skeletal muscle as the body moves. Because most veins must move blood against the pull of gravity, blood is prevented from flowing backward in the veins by one-way valves.
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