Finger slingshot

Elastigirl took off her helmet, revealing her feminine face on her manly body. She looked around quickly, stretching her neck to scan the dirt for a rock. She spotted something and bit it, retracting her head back into her neck in a matter of seconds. With her helmet back on, she began to fidget with the rock with her fingers.

It was a angular rock with sharp edges to it. She tightened her fingers, making them loose as rubber string, and wrapped her left index around her elongated thumb. Her middle finger kept the rock in place. Now all she had to do was decide where to aim.