Answer : d = 165 miles
Explanation :
We know that

If we travel 20.0 mph for 0.500 hour, then distance covered is 10 miles.
If we travel 40.0 mph for 1.00 hour, then distance covered is 40 miles.
If we travel 30.0 mph for 0.500 hour, distance covered is 15 miles.
If we travel 50.0 mph for 2.00 hours, then distance covered is 100 miles.
So, total distance covered will be 165 miles.