probability and sampling distributions

This is my first time posting a query. I'm doing first year Uni Psychology Stats and learnt last semester that I have to stick with the confusion, keep working away, until things become clear. This semester that clarity just doesn't seem to be happening. So I need help with some real basics. Could someone help me with how to approach a problem like the following:

Assuming population mean (can't find the symbol) = 9, computer a t-score for the following random sample and state whether the probability of obtaining such a t-score is greater than or less than .05.

7 7 8 8 9 9 10

Part of my confusion is simply the mathematical symbols used. It is a totally new language to me. Does anyone know of a simple glossary anywhere.

Sincerely,

Clothilde

probability and sampling distribution confusion

Thank you Mr Fantastic. I'll read the info and suspect I'll then have further questions.

Clothilde