A friend of Sam, Danni, sells canned drinks from a van in the centre of Berlin each night. Danni sold 500 drinks during one week. Each drink was sold for 3, and each one cost Danni 2. 1. How much profit did Danni make that week? 2. If Danni had bought 550 cans to sell during that week, how much would Danni's bank balance have increased or decreased in that week? 3. If, during that week, Danni bought a fridge for 280, how would that affect his bank balance? 4. Would the purchase of the fridge affect his profits?