What are the names of the forces affecting objects on Earth

i was given the task to craete a magazine article about richard hammonds dragster crash but i have to use the topic P4 to include force diagrams but i just simply dont know how the forces caused the crash in the first place

if two forces are the same size and in opposite directions, they are?

This is all about Balancing act. And I need to know it for my homework so if you know the answer can you just help please thank you.........:)........... And one more question..... What W is the amount of forces with which gravity is pulling down something?................And once more thank you!!!!!!!!!!!!!1111......:D