7. Working out brackets 5(a + c)
6. Multiplying and subtracting terms 3p*12q - 9p*-7q
8. Powers and letters a^2 * a^3 
6. Multiplying and subtracting terms 3p*12q - 9p*-7q
8. Powers and letters a^2 * a^3
Exercises
Unfortunately, at the moment there are no exercises available.
It is planned as a future functionality.