The border is locked

You have several guns at your disposal and the ability to call in airstrikes. Hold back the pressure of the enemy tank army for a given time, do not allow the enemy to reach the border. In the top view, view the entire battlefield, select the desired cannon to attack and click on it. For every 100 points scored, the possibility of calling one airstrike is added. After calling the airstrike, you will be shown a field plan and a bombing area. Move the bombing area to the right place on the battlefield - there will be a drop of bombs. If the tank has reached the border, the level is considered lost.