The specific heat capacity of the given substance is -0.66 J/g°C.
<u>Explanation:</u>
The heat absorbed by any substance is the product of its mass, specific heat capacity and change in temperature.
q = m × c × ΔT
m is the mass in grams
q = amount of heat released or absorbed in J
ΔT = change in temperature in °C = 5 -50 = -45°C
c = specific heat capacity in J/g°C
c = 
Plugin the values, we will get,
c = 
= -0.66 J/g°C
It can be anything with a big heat capacity like water
How are you going to experiment means how will you show your project in a real life situation like a penny being cleaned with different acids.
A is your answer.
On the periodic table the atomic number is the number of protons inside the nucleus.
I believe the answer would be Neutrons