Could someone explain b and c please?

Question 4: Decision making- limiting factors Wong Ltd manufactures four products using the same machinery. The following details relate to its products $28 $30 S 6 S 4 $ 3 $42 S 6 S 8 S 6 16 S 6 $45 Selling price Direct material Direct labour Variable overhead Fixed overhead Profit S 4 S 3 $ 8 $ 9 Labour hours used Machine hours used Maximum demand per week in units 2 4 250 2 4 200 180 100 Fixed overheads are absorbed based on budgeted labour hours of 1 000 per week. There is a maximum of 2 000 machine hours available per week. Required: show all your workings Question 4: Decision making- limiting factors Wong Ltd manufactures four products using the same machinery. The following details relate to its products $28 $30 S 6 S 4 $ 3 $42 S 6 S 8 S 6 16 S 6 $45 Selling price Direct material Direct labour Variable overhead Fixed overhead Profit S 4 S 3 $ 8 $ 9 Labour hours used Machine hours used Maximum demand per week in units 2 4 250 2 4 200 180 100 Fixed overheads are absorbed based on budgeted labour hours of 1 000 per week. There is a maximum of 2 000 machine hours available per week. Required: show all your workings