I need help with these two problems in a hurry. Thanks very much!!

1. The Gateway Arch in St. Louis was designed by Eero Saarinen and was constructed using the equation: y=211.49 -20.96 cosh .03291765x for the central curve of the arch, where x and y are measured in meters and lxl < or equal to 91.20.

so the question is how do I graph the central curve.

2. Verify that the function y=f(x)= T/pg cosh (pgx/T) is the solution of the differential equation d^2y/dx^2 = pg/T squareroot 1 + (dy/dx)^2