Answer:
r = 4.24x10⁴ km.
Explanation:
To find the radius of such an orbit we need to use Kepler's third law:

<em>where T₁: is the orbital period of the geosynchronous Earth satellite = 1 d, T₂: is the orbital period of the moon = 0.07481 y, r₁: is the radius of such an orbit and r₂: is the orbital radius of the moon = 3.84x10⁵ km. </em>
From equation (1), r₁ is:
Therefore, the radius of such an orbit is 4.24x10⁴ km.
I hope it helps you!
Answer: 3.33 m/s
Explanation:
Assuming the questions is to convert 12 km/h to meter per second (m/s), let's begin:
In order to make the conversion, we have to know the following:

And:

Keeping this in mind, we can make the conversion:

Then:

40 miles/hour
Details:
after one hour they have traveled 40mi. So they have traveled 40mi. in 1hr, or 40mi/1hr or 40mi/hr.
the problem is about reading a graph. the graph says that they traveled 40 miles in the first hour
formula for average speed:
miles traveled/time it took=speed or d/t=r