40.If you are flying in an airplane at an altitude ofh

h

miles, on a clear day you can see a distance ofd

d

miles to the horizon, whered

=

7920

h

.

d=7920h.

a.Write the formula fordas a power function in the formf(x)=kxp

b. Choose a reasonable domain for the functiond=f(h)and graph the function.

1. At what altitude will you be able to see for a distance of100miles? How high is that in feet?
2. 51.Match each function with the description of its graph in the first quadrant.f(x)=x2
3. f(x)=x2
4. f(x)=x2
5. f(x)=x1/2
6. Increasing and concave up
7. Increasing and concave down
8. Decreasing and concave up
9. Decreasing and concave down