QUESTIONS! PLEASE ANSWER ALL WITH WORK AND I WILL UPVOTE, THANKS!

Zales Jewelers uses rubies and sapphires to produce two types of rings. A Type 1 ring requires 2 rubies, 3 sapphires, and 1 hour of jeweler's labor. A Type 2 ring requires 3 rubies, 2 sapphires, and 2 hours of jeweler's labor. Each Type 1 ring sells for $400, and each Type 2 ring sells for $500. All rings produced by Zales can be sold. Zales now has 100 rubies, 120 sapphires, and 70 hours of jeweler's labor. Extra rubies can be purchased at a cost of $100 per ruby. Market demand requires that the company produce at least 20 Type 1 rings and at least 25 Type 2 rings. To maximize profit, Zales solved the LP below. Use the computer output to answer the questions. X1= Type 1 rings produced X2= Type 2 rings produced R= number of rubies purchased 1) max400X1+500X2100R subject to 2) 21+32R=20 6) X2>=25 LP OPTIMUM FOUND AT STEP OBJECTIVE FUNCTION VALUE 1) 19000.00 RANGES IN WHICH THE BASIS IS UNCHANGED: (a) Suppose that Zales were only required to produce at least 23 Type 2 rings. What would Zales' profit now be? Answer: $ (b) Suppose that instead of $100, each ruby costs $190. Would Zales still purchase rubies? If yes, what would be the new optimal profit? If no, write NO. Answer: \$ (c) What is the most that Zales would be willing to pay for another ruby on top of the regular price? (i.e.. what's ruby's shadow price?) Answer: (d) What is the most that Zales would be willing to pay for another ruby (total, including the regular and shadow price)? Answer: $ (e) Zales is considering selling a new jewelry set consisting of 2 rubies and 2 sapphires. What should be the minimum selling price on this set for this to make sense