Help with this much appreciated:

Sub Stop, a small sandwich store, is located on a busy corner near many other businesses. The shop's busiest time is during the mid-day period. Rent for the location is $1100 per month, and wages amount to $2100 per month. Variable costs consist of supplies and sandwich ingredients that cost $2.03 per sub sandwich. The subs are to be sold at a price of $5.49 each. Answer each of the following independent questions. (a) How many sandwiches must the shop sell to break even? (b) If the shop increases variable costs by $0.25 per sandwich, how many sandwiches must it sell to break even? (c) If the rent increases by 11%, what would the profit be if the shop sold 1554 units? (d) If the sandwich price was reduced by $0.25, how many sandwiches must the shop sell to make $1168 profit