1. **State the problem:** We have a right triangle with one angle of 56° and a right angle of 90°. We need to find the unknown angle $f^\circ$. 2. **Formula used:** The sum of angles in any triangle is always 180°. So, $$56^\circ + 90^\circ + f^\circ = 180^\circ$$ 3. **Solve for $f^\circ$:** $$f^\circ = 180^\circ - 56^\circ - 90^\circ$$ 4. **Calculate:** $$f^\circ = 180^\circ - 146^\circ = 34^\circ$$ 5. **Conclusion:** The unknown angle $f^\circ$ is $34^\circ$. This matches the answer option 34°.