Please this is a test

Which expression is equivalent to 5r6141 2r+st6

One of the same side angles of two parallel lines is 20° smaller than the other one. find the measures of these two angles.

Determine whether the quadrilateral below is a parallelogram. justify/explain your answer (this means back it up! give specific information that supports your decision. writing just "yes" or "no" will result in no credit.)