Describe what happens when
a. two plates carrying oceanic crust collide,
b. two plates carrying continental crust collide, and
c. a plate carrying oceanic crust collides with a plate carrying continental crust.
plz

If the 2 plates carrying oceanic crust collide, one goes underneath the other causing a tsunami or or an underwater earthquake

If the 2 plates carrying continental crust collide, the collision squeezes the crust into mountain ranges

When a plate carrying oceanic crust collides with a plate carrying continental crust the denser oceanic plate subducts below the continental plate

This is all you, but i can give you some topics that you could try. if it rained when you want to do something outdoors, it 'limits' that human activity. maybe you want to do an experiment that goes throughout the whole year and you have to have above freezing the entire year. this 'limits' your activity. i thought of those just off of the top of my head. something that gets to me that might be getting to you is you are thinking too hard about what to do. think simply, and if it is too simple, then bump it up just a little bit.