Answer:
well physical weathering is the process of a element or acts of water rock or other items that take its toll on items
Explanation:
so i would,WITH CONFIDENCE C.
B. The surface of a silver cup turns black when it is exposed to air.
Explanation:
As the given chemical reaction equation is as follows.

Also, it is given that for 2 moles the energy required is 130 kcal. This means that energy required for 1 mole is calculated as follows.
1 mole = 
= 65 kcal
Hence, energy required for 7 moles will be calculated as follows.
Energy required = 
= 455 kcal
Thus, we can conclude that energy required to produce 7.00 mol
on the basis of given reaction is 455 kcal.
Answer:
<u>The answer is</u>: <em>B. </em><em>Energy lost to the environment during the reaction must be replaced.</em>
Explanation: