can someone help me solve the problem below

Problem: A suspension bridge with weight uniformly distributed along its length has twin towers that extent 90 feet above the road surface and are 600 feet apart. The cables are parabolic in shape and are tangent to the road surface at the center of the bridge.

a.)What is the value of P?

b.)What equation refers to the suspension bridge if the vertex is located 200 feet away from the origin and it lies at the x-axis?

c.)How high is the cable 180 away feet from the center?