Answer:
B. 4.8 miles per hour
Explanation:
We are given that,
Distance needed to walk by Danielle = 4 miles
Time needed to reach the destination = 50 minutes = 0.83 miles
It is required to find the speed needed by Danielle.
Since, we know,

i.e.

i.e. Speed = 4.8 miles per hour
Hence, she needs to walk 4.8 miles per hour to reach her destination.