Here in order to find out the distance between two planes after 3 hours can be calculated by the concept of relative velocity

here
speed of first plane is 700 mi/h at 31.3 degree


speed of second plane is 570 mi/h at 134 degree


now the relative velocity is given as


now the distance between them is given as



so the magnitude of the distance is given as

miles
so the distance between them is 2985.6 miles
Explanation:
the correct answer is Option 5.√½gh.
hope this helps you.
KE=0.5 * mass* speed^2
Convert 72 km/h to m/s by dividing it by 3.6
72/3.6= 0.277778m/s
KE=0.5*1500*0.277778
= 208.3335J
= 208J
Answer:
A
If Car A has half the mass of Car B, then it must have twice the velocity to come to a stop when colliding.