There are 4 quarts in a gallon. In addition, there are two pints in every quart, so we have 4*2=8 pints. There are 2 cups in a pint, so there are a total of 8*2=16 cups in one gallon.
I believe your answer is:
<span>C. Two times r equals the diameter of the circle. Pi is needed for all circle formulas, so you multiply by Pi since you are finding the circumference.
2r = d or, 2 radius = one diameter
</span>π is used in both circle equations:
<span>
2</span>πr (circumference)
πr² (area of circle)
hope this helps