The answer is the last one; to express very large or small numbers.
We use it so we can show big or very small numbers in an easier way.
Use Stokes' theorem for both parts, which equates the surface integral of the curl to the line integral along the surface's boundary.
a. The boundary of the hemisphere is the circle
in the plane
, where the curl is
. Green's theorem applies here, so that

which means the value of the line integral is 3 times the area of the circle, or
.
b. The closed sphere has no boundary, so by Stokes' theorem the integral is 0.
Actually it's
y =

it's a line. so 2 points is enough
choose x so that x+4 would be divisible by 3 :)
1) x = 2, then y = (2+6) / 3 = 2 - sketch point (2,2)
2) x = 5, then y = (5+4) / 3 = 3 - sketch point (5,3)
3) line goes though those points. use ruler :)
3 x 2 = 6 cups of concentrate
3.5 x 3 = 10.5 cups of water
Bob can make 6 cups of orange juice.
Mechanical Advantage = Force by Hammer / Force by Nail = 160/40 = 4