all bullet points please help show all work woukd be great for me

Toothpaste is a necessary, frequently purchased consumer product. In an average week a retailer sells 200 tubes at $4,25 per tube, a single tube costs the retailer $3.00 Sometimes the retailer reduces the selling price by .50 cents for a one week sale. Historical data tells the retailer that for two weeks after the sale (i.e., now back to full price), the number of tubes sold will be down by 10%. Please show your work: What is the non-sale gross margin percent? What is the sale price gross margin percent? How many tubes will the retailer need to sell during the sale week to be at least break even over the full three week period (the sale week and the next two weeks)