Triple Integrals and Mass?

Question

I am completely stuck as to how to set up this equation, If you could help me get started, I would really appreciate it!
Find the mass of the region (in cylindrical coordinates) r^3≤z≤5 , where the density function is ρ(r,θ,z)=3z .

Answer 1

differential volume in cylinrical coordinates dV = rdrdzdq (q = theta)

SInce density not dependent on angle integral over dq = 2pi

m = 2pi*Sdz Srho rdr
density not dependent on r so last integral becomes

m = pi r^2 Srho dz = pi r^2 S3z dz = 3/2 pi r^2 [z^2]

In brackets is evaluated at z = 5 and z = r^3

m = 3/2 pi r^2 (25 - r^2)