Answer:
a)22.2°C after adding magnesium
b)17.3°C before adding magnesium
c) 4.9 is change
Explanation:
Using stratified random sampling, researchers must identify characteristics, divide the population into strata, and proportionally choose individuals for the representative sample. ... For example, individuals who are too busy to participate will be under-represented in the representative sample.
In order of increasing percent water content:CoCl₂.6H₂O, Ba(OH)₂.8H₂O, MgSO₄.7H₂O
<h3>Further explanation</h3>

CoCl₂.6H₂O.MW=237.90 g/mol
6H₂O MW = 6.18=108 g/mol

MgSO₄.7H₂O.MW=246.48 g/mol
MW 7H₂O = 7.18=126 g/mol

Ba(OH)₂.8H₂O MW=315.48 g/mol
MW 8H₂O = 8.18=144 g/mol

The type of reaction in above reaction is refered to as a disproportionation reaction .It sometimes used to describe desymmetrizing reaction.in the equation above compounds of intermediate oxidation state are converted to two different compound, that is Clo3 ions and 2cl-