The value of C would be 25
5 lbs. = 80 oz.
80 - 12 = 68 oz.
68 / 4 = 17 bags
Hope this helps!
The formula for the area of a sector in radians is

, where theta is the angle in radians. For us, the formula looks like this:

. Doing all the multiplication on that gives us

. Multiplying in pi and rounding to the nearest tenth gives us an area of 76.3 meters squared. You can use the formula for the area of a sector with the angle in degrees as well. Just replace the 360 degrees with 2pi and it works the exact same way.