Answer: 8/5 mph
Explanation:
According to definition, an object's speed is determined by:
s=d/t where,
d is the object's travel distance, and t is the amount of time it takes.
We can replace these values with:
Since, s= (4/5) / (1/2) mph
=> s= 8/5 mph
The object's speed to cover 4/5 miles in 30 minutes is: 8/5 mph