Answer : The specific heat of the metal is, 
Explanation :
In this problem we assumed that heat given by the hot body is equal to the heat taken by the cold body.


where,
= specific heat of metal = ?
= specific heat of water = 
= mass of metal = 97 g
= mass of water = 122 g
= final temperature of mixture = 
= initial temperature of metal = 
= initial temperature of water = 
Now put all the given values in the above formula, we get


Therefore, the specific heat of the metal is, 
Answer:
A. They would have observed a radioactive signal in both the pellet and the liquid.
To get the empirical formula of this compound, we take a basis of 100 grams which means each percentage is equivalent to 1 gram. Hence there is 32.39 grams sodium, 22. 53 grams sulfur and 45.07 grams oxygen. We convert each mass to their moles by dividing by their respective molar mass. Na: 1.408, S:0.704 and O:2.82. divide each with the lowest: Na: 2: S: 1 and O:4. Hence the formula is Na2SO4.