The escape velocity on the surface of earth is 11.2 km/s. If earth has mass 9 times the mass of Mars and radius equal to twice the radius of Mars, calculate the minimum velocity required by a projectile to escape the gravitational field of Mars.

Explanation

To find the minimum velocity required by a projectile to escape the gravitational field of Mars, we can use the relationship between the escape velocities of Earth and Mars, given the mass and radius of both planets.

### Step-by-Step Solution:

1. **Understand the escape velocity formula**:
The escape velocity \( V_e \) from a celestial body is given by the formula:
\[
V_e = \sqrt{\frac{2GM}{R}}
...