Explanation:
The first question is pretty straight forward, all you have to do is get a ruler and measure how long XY is. Then draw another line that has the same exact length next to it and label it AB, by drawing A and B at the end points like how they did in the line XY
For the second question measure the length of FG and then measure the length of YZ and add the two lengths and then draw a line with that length and then label it CD by labeling the end points C and D.
For the last question measure the length of MN and then divide that length in 2 and then label that midpoint O. for example if I had the same problem and I put my ruler on the line and saw the length was 10 inches, I would go to where it's 5 inches and label the midpoint on the line. You also want to draw a perpendicular line through that midpoint O.