Second Part Final (4 Problems Need Help)

Hello,

Well I think I did fairly well on my first part of the math final. Well I've been studying for my second part of the final which is wednesday night. I have 4 problems this time I need help with, everything else is going smooth. Thanks for the help on the previous post i understand those pics were hard to make out lol. Well anyway here goes nothing...

#28) A fourth grade class decides to enclose a rectangular garden using the side of the school as one side of the rectangle. What is the maximuum area that the class can enclose with 32 feet of fence? What should be the dimensions of the garden be in order to ield this area?

#30) Maximizing Area: The sum of the base and the height of a parallelogram is 69cm. Find the dimensions for which the area is a maximum.

#32) (confused me like crazy) Finding the Height of a Cliff: A water balloon is dropped from a cliff. Exactly 3 sec later, the sound of the balloon hitting the ground reaches the top of the cliff. How high is the cliff? (maybe this will help: t1 + t2 = 2) (maybe this will help too s=16t /\ 2 t is seconds and time is t1 that it takes the tablet to hit the water can be found as follows s=16(t1)/\2

lastly #38) Norman Window. A Norman window is a rectangle with a semicircle on top. Sky blue windows is designing a Norman window that will require 24 feet of trim. What dimensions will allow the maximum amount of light to enter a house? (maybe this will help) when looking at a normal window you see a rectangle with a half circle attached to the top. the x-axis is the top of that rectangle flowing horizontally and the y-axis is the side of that rectangle flowing vertically.

any help would be much appreciated before 3:30pm wednesday eastern time. Sorry for the late notice its been a hectic week :)