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.3. The following problems must be solved using the methods learned in class. No marks for guessing (4) 4. A lifeguard wishes to enclose a rectangular swimming area on a beach using 400 m of oating line. The beach will serve as the fourth side of the rectangle. Calculate the ,I dimensions of the rectangle that will maximize the swimming area. (5) 5. Be-like-Mike golf clubs usually sell for $1300. At this price, the retailer can sell, on average, 20 sets per week. For every $50 reduction in price, they sell 2 more sets per week. Similarly, for every $50 increase, they sell 2 sets less per week. Determine the optimum price to maximize their weekly revenue. .4. t (5 6. A large cylindrical tank with volume 321: m1 is to be constructed from two different .\\ materials. The top and bottom are to be made from a special alloy that costs $20/m', while {3 j the material for the sides will only cost $10/m2. Find the dimensions of the cylinder that \\ 77/ will minimize the cost of the materials. Determine the area of the largest rectangle that can be inscribed between the x-axis and the curve dened by y = 16 - x1 (4)