OK these are the PreTest problems my teacher has laid out for me, help with any would be greatly appreciated!!!

1. Show that for the function F(a), that a is the centered difference of h-a & h+a

2. a. Use centered difference to find f'(1.2)
b. Use f'(1.2) to estimate f(1.3)

x | y
--------
1.0 .98
1.1 1.35
1.2 1.80
1.3 2.05
1.4 1.85

3. Find the max and min on the interval -2 < x < 4 for
y= x/1+x^2

4. If N(30)=470
and N'(30)=6
Approximate N(35)

5. Find the local max and min of

y=(6-5x-x^2)^4

6. The price of an Acme Widget is given by P-100-2x dollars when x Widgets are sold. The cost per Widget is 20-radical (x) [sorry dont know how to do the square root sign] when x Widegets are made. Assuming you sell everything you make, how many Widgets sold will maximize profit?

7. A piece of wire 24 inches long is cut to make a square and a circle. Hwo should it be cut to maximize area?