What causes a rockslide the quick movement of rocks down a slope ?
science

Gravitational force starts it, gravitational acceleration gives it speed and inertia keeps its direction. 

Well, a combination of gravity and water loosens the rocks and causes them to start sliding down. As they fall the force of gravity causes the rocks to fall faster and faster, bringing more rocks down. This is how rockslides can destroy entire houses.
Hope this helps!

Depends,

health tests should be required

but I dont agree with the c vaccine.

But yes, drug tests should be required if they dont do any serious harm and if its for health

(PoeticAesthetics keeps deleting my answers for no reason so i wrote this again)