Well let’s put it this way. To find the neutrons you subtract the atomic atomic Nuremberg from the atomic mass. So
Mass=81-Number=28
81-28=53
Final answer is 53.
Let the rescue boat starts at an angle theta with the North
now its velocity towards East is given as


now in some time "t" it will catch the boy
so we will have

also we have

now we have



by solving above we got

Answer:
For other liquids, solidification when the temperature drops includes the lowering of kinetic energy, which allows molecules to pack more tightly and makes the solid denser than its liquid form. Because ice is less dense than water, it is able to float at the surface of water.
Explanation:
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