Algebraic Expressions Exponents

help me prepare for my maths exam!?
it my maths test on Monday and the topics are (class 8 student)
squares and square root,cubes and cube roots,exponents,algebraic expressions(polynomials),identities,linear equations,rational numbers
so which is the most scoring topic and what are the main thing in those topics which comes in the exam many times.
polynomials and rational numbers are the scoring part if you know the formula and small tricks.
Though many feels rational numbers are tough with basic logic any one can score full mark in that topics.
Rest all you can. I hope you can.
Tips: Have all the formula in the long sheet of paper and prepare those whenever you get time, mainly before entering the exam hall but remember to leave it outside before you enter.
All the best for your exams.
Simplifying Algebraic Expressions Involving Exponents

