Answer:
Newton's First Law of Motion applies here.
Step-by-step explanation:
Before crashing into the fence, Amy was moving at a certain speed on her bike. As, she crashed her bike into the fence, the collision stopped the bike suddenly. But, Amy had the same speed due to inertia of her body. Due tot his speed Amy did not stop and she was thrown over the fence onto the lawn. So, the force of inertia of Amy's body caused her to be overthrown in this case. We study about inertia in Newton's First Law of Motion, which is also known as Law of Inertia.
Newton's First Law of Motion applies here.