Answer:
True.
Explanation:
An exothermic reaction has a positive enthalpy (heat) of reaction. However, it can be negative in some circumstances.
C) Noble gases
The six noble gases are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn). Their atomic numbers are, respectively, 2, 10, 18, 36, 54, and 86.
Dont know the first part but melanin quantities change the dkin color
