If SP is equal to rupees 400 and loss percent is 20% find CP​

In the image, point a marks the center of the circle. which two lengths must form a ratio of 1 : 2? (options are in the images since thought they were harmful phrases)

In trapezoid efgh, m∠hef=(4x2+16)∘ and m∠gfe=(5x2+12)∘. find the value of x so that efgh is isosceles.

On a architect's drawing of a house, 1 inche representa 1.5