1) Carbon-13:
Proton-6 Neutron-7 Electron-6
2)Atomic mass of element X:
(55*10+56*20+57*70)/100=56.6
You have to do a report :

So
the truck efficiency is 38%.
However, Duncan has prepared ramen noodles so many times he does not need to measure the water carefully. If he happens to heat 0.850 ...
Answer:
The melting point range of a substance is the temperature range from which the first crystal starts to melt, to the temperature at which the last crystal finishes melting. An impure substance is a type of mixture, so melting points can be used to find out if a substance is pure or impure.
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Explanation: