It would be D because the formula is: pi r^2
She brings 3 donuts because a dozen is 12 and 1/4 of 12 is 3.
1.65 + 0.85x= $20
0.85x=$18.35
x=21 10/17
first you write the equation
then you have to subtract 1.65 from the equation but you also have to subtract it from 20
then you divide 0.85 from 0.85x and from the 18.35 left over from subtracting 1.65 from 20
then you should get x=21 10/17 (simplified) but the decimal form is a ongoing fraction so you can just round it up to the nearest hundredth
Use the Pythagorean therm , you know the a^2+b^2=c^2
