Answer: c = 2
Step-by-step explanation: Solve for c by simplifying both sides of the equation, then isolating the variable.
(7.8×10⁷)+(9.9×10⁷)
(7.8×10000000)+(9.9×10000000)
(78000000)+(99000000)
177000000
The answer would be 32 miles (I think) if you set up a proportion you should get this answer.