They use common poppy melodies. They sound like most other pop songs.
Triple integrals aren’t that bad…
dH=C*dT+V(1-αT)dP where dH is the heat content. This can be negative if α is negative. α can be negative if δV/δT is negative (The change in Volume with respect to time).
Not sure if my answer for six is right or not but if you alternate adding and subtracting the numbers you get twelve: