As shown in above figure which of the following angles are equal
Four cannon balls, '1', '2', '3' and '4' are fired from level ground. Cannonball '1' is fired at an angle of 60∘ above the horizontal and follows the path shown.
Cannonballs '2' and '3' are fired at an angle of 45∘ and '4' is fired at an angle of 30∘ above the horizontal. Which cannon ball has the largest initial speed?