It is a constant-volume type calorimeter that measures the heat of a particular reaction or measures the calorific value of the fuels. Bomb calorimeters are built in such a way that they can withstand the large pressure produced within the calorimeter due to the reaction or burning of fuel.
It would be D since it could be unhealthy for you.
Because metals that are more reactive than carbon wont react with it.
Explanation:
Depression in Freezing point
= Kf × i × m
where m is molality , i is Van't Hoff factor, m = molality
Since molality and Kf remain the same
depression in freezing point is proportional to i
i= 2 for CuSO4 ( CuSO4----------> Cu+2 + SO4-2
i=1 for C2h6O
i= 3 for MgCl2 ( MgCl2--------> Mg+2+ 2Cl-)
So the freezing point depression is highest for MgCl2 and lowest for C2H6O
so freezing point of the solution = freezing point of pure solvent- freezing point depression
since MgCl2 has got highest freezing point depression it will have loweest freezing point and C2H6O will have highest freezing point