Find the solution using polymath software

A heat exchanger is required that will be able to handle a maximum water flow (Q) of 2.5 Ls at 30C(g= 995.7kg/m3,=0.0008kg/m.s ) through a smooth pipe with an equivalent length (L) of 100m. The maximum pressure drop across the exchanger is 103kPa. What diameter (D) pipe would you recommend for this job? One approach to this problem is to simultancously solve the following three equations for the friction fictor (f), the velocity through the pipe (v) and the pipe diameter (D). 1/f=4.0log10(Rev/)0.4P=2fPv2/DQ=vD2/4 (1)