True or False: "A graph of a linear equation forms a line which starts and stops at certain points"

In the coordinate plan (-6,9) b (3,9) c (3,3) def is shown in the coordinate plan below

The given dot plot represents the average daily temperatures, in degrees fahrenheit, recorded in a town during the first 15 days of september. if the dot plot is converted to a box plot, the first quartile would be drawn at __ , and the third quartile would be drawn at link to the chart is here

Write the sine and cosine values of a, b, respectively, in the figure for (1) and (2) + explanation.