ONLY P2P DISTRIBUTION please explain how to go about the integral portion

Consider distributing a file of F=20 Gbits to N peers. The server has an upload rate of Us=50 Mbps, and each peer has a download rate of d;=5 Mbps and an upload rate of u. For N=10, 100, and 1,000 and u=300 Kbps, 700 Kbps, and 2 Mbps, prepare a chart giving the minimum distribution time for each of the combinations of N and u for both client- server distribution and P2P distribution. b. P2P a. Dpap = max and in ustzia 10 100 1000 300 Kpbs 700 Kbps 2 Mbps