A race car fan is standing in one spot cheering . The race car is 10 feet away from fan when it is in the starting line and 50 feet from them when on the opposite side from the fan. The race car takes 60 seconds to make a complete rotation. At time 𝑡 = 0, the race car is in the starting line, (0, 10). The sinusoidal function 𝑓 models the distance between the race car and the fan, in feet, as a function of time, in seconds.
The function 𝑓 can be written in the form of 𝑓(𝑡) = 𝑎 sin(𝑏(𝑡 + 𝑐)) + 𝑑.
Find the values of the constants 𝑎.