Answer:
from which language this belongs to
Answer : The reaction is endothermic.
Explanation :
Formula used :

where,
= change in temperature = 
Q = heat involved in the dissolution of KCl = ?
m = mass = 0.500 + 50.0 = 50.5 g
c = specific heat of resulting solution = 
Now put all the given value in the above formula, we get:


The heat involved in the dissolution of KCl is positive that means as the change in temperature decreases then the reaction is endothermic and as the change in temperature increases then the reaction is exothermic.
Hence, the reaction is endothermic.
Answer:
A) involves changes in temperature
Explanation:
The figure is missing, but I assume that the region marked X represents the region in common between Gay-Lussac's law and Charle's Law.
Gay-Lussac's law states that:
"For an ideal gas kept at constant volume, the pressure of the gas is directly proportional to its absolute temperature"
Mathematically, it can be written as

where p is the pressure of the gas and T its absolute temperature.
Charle's Law states that:
"For an ideal gas kept at constant pressure, the volume of the gas is directly proportional to its absolute temperature"
Mathematically, it can be written as

where V is the volume of the gas and T its absolute temperature.
By looking at the two descriptions of the law, we see immediately that the property that they have in common is
A) involves changes in temperature
Since the temperature is NOT kept constant in the two laws.
A. They speed up chemical reactions