For part (a) plug this into your calculator:

For part (b):

The maximum intensity of the light is observed when you are 0 meters away from the car. So you would need to solve this equation:

This implies that

For part (c):

We want to find :

My next step would vary, depending on your interpretation of logs. When you say log, are you referring to or ??

I will show both ways, and you pick the one that fits the context of log in this problem.

If represents , then

If represents , then

I hope this makes sense!

--Chris