Answer:
Their contact will end after 2 hours.
Step-by-step explanation:
Let east be positive and west be negative.
The first team travels east at 20 miles per hour.
Speed of first team = 20 mph
The second team travels west at 25 mph
Speed of second team = -25 mph
Relative speed = 20- (-25) = 45 mph
Range of radio = 90 miles
We need to find how long will it be before they lose radio contact.
Distance = Time x Speed
90 = Time x 45
Time = 2 hours
Their contact will end after 2 hours.
