I'm having trouble understanding, can someone please give an explanation I don't get it when the line is going straight across

Consider the proof. given: segment ab is parallel to line de. prove: what is the missing statement in step 5?

Determine which postulate or theorem can be used to prove that lmn =nmo

The bottom of ignacio's desktop is 74.5cm from the floor. ignacios sits in his adjustable chair, and the tops of his legs are 49.3cm from the floor. each clockwise rotation of the knob on the chair raises ignacio's legs by 4.8cm. write an inequality to determine the number of clockwise rotations, r, ignacio could make with the knob without his legs touching the desk.