I got this problem from my teacher and don't know how to solve, could someone please help?
(SAT Prep) In △ABC, ∠B = 90°, BH = AH, and the ratio of m∠A to m∠C is 1:2. Find m∠BHA?
A. 100°
B. 90°
C. 120°
D. 60°
I know that m∠A = 30°, and that m∠C = 60°

$\triangle BAH$ is isosceles because it has two equal sides.
This means that $m(\angle BAH) = m\angle ABH$ because of base angle theorem.
Then, $m\angle BHA = 180 - (m(\angle BAH) + m(\angle ABH))$ (because the sum of the measures of the angles in a triangle is $180$)
But since $m(\angle BAH) = m(\angle ABH) = 30$, we simply have
$m(\angle BHA) = 180 - (30 + 30) = 120$