Final answer:
The optimum angle at which a projectile should be launched in order to cover the maximum distance is 45°.
Step-by-step explanation:
In physics, the optimum angle at which a projectile should be launched in order to cover the maximum distance (range) is 45°. This is known as the launch angle that maximizes the range of a projectile on level ground.
When launching a projectile, the range is determined by the combination of the initial velocity and the launch angle. If the launch angle is too low, the projectile will not reach a far distance. If the launch angle is too high, the projectile will spend more time in the air but also not cover a great distance.
Therefore, the launch angle of 45° provides the best balance between the initial velocity and the time of flight, resulting in the maximum range.