Answer:
A. ∠ QPR = 17°
Step-by-step explanation:
From the given information, let QP be the length of the ramp.
Then, ∠ QPR is the angle between the ramp and the ground.
∠ PQR is the angle between the ramp and the doorpost and
∠ QRP is the angle between the doorpost and the ground.
Clearly, ∠ PQR = 73° (given)
∠ QRP = 90° (since doorpost and the ground are perpendicular to each other)
Now, use triangle sum propoerty of ΔQPR, we get,
∠ QPR + ∠ PQR + ∠ QRP = 180°
∠ QPR + 73 + 90 = 180°
∠ QPR + 163 = 180°
∠ QPR = 180 - 163
∠ QPR = 17°
