65 because if you put all the numbers in order and work out which one is in the middle you get the median. i enjoy using the rhyme. Hey diddle diddle, the medians the middle, you add then divide for the mean, the mode is the one that you see the most and the range is the difference between.
101 feet. also -1 isnt an elevation. If you were to draw a line youd put all the negative numbers on the bottom, and positive on the top.
Since they're vertical angles, they're equal in degree measure
since they're equal, we can make the two expressions equal to each other
5a - 1 = 2a + 20
add 1 to both sides
5a = 2a + 21
subtract 2a from both sides
3a = 21
divide both sides by 3a
a = 7
now, plug the answer you found for a into one of the two expressions
5a - 1 becomes (5*7) - 1, which equals 34
to double check that they're equivalent (since they're vertical angles)
2a + 20 becomes (2*7) + 20, which equals 34
both angles are 34 degrees!