Alarge sphere has a mass of 175 kg and is suspended by a chain from the ceiling. the mass of the chain is 12.0 kg. what is the tension in the chain?
1830, n1610, n1720, n1940 n.

Each point in the chain supports the weight of all the mass below it.

At the bottom end of the chain, the weight is  (175 x 9.8) = 1,715 N .
At the top of the chain, the weight is  (175 + 12) x (9.8) = 1,833 N .

The tension in the chain varies linearly from  1,715N  at the bottom
to  1,833N  at the top.

Your answer would be the sun 

Repeated trials allow you to calculate a mean which can reduce the effect of random errors to make your results more precise.your results will also be reproducible therefore if someone else did the same experiment they'd get the same results which would make your results more reliable.