RICAS Grades 6-8 Geometry. Practice it free.

$180 - 45 = 135°$.

The circumference of a circle is $C = \pi d$. Substitute $d = 20$: $C = \pi(20) = 20\pi\textsf{.}$

Trapezoid area $= \dfrac{1}{2}(b_1 + b_2) \cdot h = \dfrac{1}{2}(7 + 10) \cdot 6 = \dfrac{1}{2}(17) \cdot 6 = 51$.

$A = \pi r^2 = 3 \times 9 = 27$.

$V = \ell w h$ and $\ell = 2w$, so $160 = (2w)(w)(5) = 10w^2$. Then $w^2 = 16$, so $w = 4$ and $\ell = 8\text{ in}\textsf{.}$

The two triangular faces have total area $2 \times \dfrac{1}{2}(3)(4) = 12$. The three rectangular faces have areas $3(10) = 30$, $4(10) = 40$, and $5(10) = 50$, where $5$ is the hypotenuse. The total is $12 + 30 + 40 + 50 = 132$ square inches.

$V = \pi r^2 h = 3 \times 4 \times 4 = 48$.

$V = 2 \times 5 \times 6 = 60$.