I am confused about these

A rectangular garden is to be fenced off. You have 98 feet of fencing to be used to fence off three sides the rectangular garden as a wall makes up the fourth side. What dimensions will produce the garden with the biggest area?2. Find the value of x such that the Mean Value Theorem is satised for x) : L over 1 x the interval 2 S x S 3 . Ifthere is no such value, state so. 3. The radius of a sphere is increasing at a constant rate of 2 metersfsecond. At what rate is the surface area increasing when the surface area is equal to the volume of the sphere? 4. An open can is dropped into a lake and oil begins to spill as a circular disk with uniform thickness whose radius increases at a constant rate of 10 mfsec. At the moment when the radius is 1 meter, the thickness of the oil is decreasing at the rate of 0.04 meters per second. How fast is the thickness decreasing when the radius is 2 meters? 17. Let f(x) = me2 it. Find a local linear approximation for f (x) at x : 0 and use it to approximate f (l) . 18. Given 1' (x) = e" at, then in terms of c, at what value of .1: does the minimum value of f(x) occur? Assume c > 0. 22. At total of x feet of fencing is to form 3 sides of a rectangular yard. What Is the maximum possible area of the yard in terms of x ?\f