Doing homework are we? None of the homework questions people have posted have been difficult, 5 minutes on google and some thinking and you can get the answer yourself and will get far more out of the assignment.
If you are going to ask stuff from your homework at least reword it so its not like a textbook question. The "why might we expect" gives it away.
Think of it like pistons in a engine in your car. 4 is better than 1, 4 can not only do more work but at the same time each one doesn't have to work as much as just one alone. With more you can get more work done and applications respond much better.