Final answer:
The correct option is b. The maximum height reached by a shell fired from the ground can be calculated using the formula h = v₀² / (2g), where v₀ is the initial vertical component of the velocity and g is the acceleration due to gravity.
Step-by-step explanation:
The maximum height reached by a shell fired from the ground with an initial speed v₀ can be calculated using the formula h = v₀² / (2g), where v₀ is the initial vertical component of the velocity and g is the acceleration due to gravity.
In this case, the correct answer is option (b) v₀² / (2g).
For example, if the initial speed is 20 m/s, the maximum height reached would be (20 m/s)² / (2 * 9.8 m/s²) = 20.41 meters.