The area in square units of the region bounded by the curve $y = \sqrt{16 - x^2}$ and lines $x = 0, x = 4$ above the X-axis is

The area of the region lying in the first quadrant and bounded by the curve $y = 4x^2$, the Y-axis, and the lines $y = 2$, $y = 4$ is...

The area bounded by the curves $y = |x| - 1$ and $y = -|x| + 1$ is

The area (in sq. units) of the region bounded by the curve $y = 2x - x^2$ and the X-axis is...