Question

1. are the lines $overleftrightarrow{ab}$ and $overleftrightarrow{cd}$ parallel?

it cannot be determined
no
yes

Explanation:

Step1: Recall parallel line rule

For two lines cut by a transversal, if they are parallel, corresponding interior angles are equal.

Step2: Compare given angles

The given interior angles are $80^\circ$ and $79^\circ$. Since $80^\circ
eq 79^\circ$, the lines do not satisfy the parallel line condition.

Answer:

B. No