Slingshot against birds

Are you tired of pigeons that constantly sit on power lines?
Then drive away all the pigeons using a powerful slingshot, but you only have 1 pebble.
This is a simple puzzle game using a slingshot mechanism.
I wonder how good a player you are?

Use the A and D buttons on your keyboard to move the slingshot left and right.
Press the spacebar to fire your slingshot.
Your task is to hit all the birds with one stone.
There are coins on the levels, hitting them, you collect them.
Coins can be used to improve the flight speed of a pebble.