The area (a) of a circle is a function of its radius (r) and is given by the function a = f(r) = πr2. what is the domain of this function?

a. all positive real numbers
b. all real numbers
c. all positive real numbers including 0
d. all real numbers excluding fractions

option a is correct.

step-by-step explanation:

scale factor: it is used to find proportional measurements.

proportions means having the same ratio.

scale factor is the ratio of the model measurement to the actual measurement in a simplest form.

or we can say that the ratio of any two corresponding lengths in two similar geometric figures

if the scale factor is more than 1, then it is an enlargement,

if the scale factor less than 1, then it is a reduction.

given the two geometric figure:

by definition of proportions, we have

c. 1,233 miles

2425

step-by-step explanation: