How many pairs of opposite sides are parallel? no pairs 1 pair 2 pairs​

Can someone me with the property questions for 12 13 and 14 plz

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.

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.