These sets of equations are a single integral that I separated to better visualize the steps. I already have the final answer to the MAPLE resolved. I wonder how the MAPLE resolves, for example, the inner integral:

B:=(1.5438E-6*A*(1307-A))/(10^(-2.623+3388.8/(A-491)))*(1-exp(-abs(51749.478-33.6521*A-0.0044809*A^2)/(8.31*A))):
G:=int(B,A=500..T):

What is the result (not numerical) this indefinite integral?
This result should be cubed, multiplied by N and integrated again (500 .. 1307) and the result substituted in Rcc.