I work through the examples in my free lectures. There is no point at all in using the notes without watching the lectures. The notes are lecture notes and it is in the lectures that I explain and expand on the notes. If you are not watching the lectures for any reason then you must buy a study text from one of the ACCA approved publishers and study from there.
The profit is 50% of the cost. How on earth can the cost be $3.50 and the profit be $7? $7 is not 50% of $3.50 !!!!