Can someone please help me out with this problem..

the towers of a suspension bridge are 800ft apart and rise 160ft above road. The cable between the towers has the shape of a parabloa and the cable just touches the sides of the road midway between the towers.

i) what is the height of the cable 100ft from a tower?

ii) what is the length of the cable between two towers?

iii) use this problem to explain why mathematicians can be an evolving discipline, interrelated with human culture, and its connection with other disciplines.

** Sorry for my bad paint drawing

Thanks a bunch