If triangle NKF is similar to triangle LZF, find NF

Which statement about perfect cubes is true

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

If x = -2, then x 2-7x+10 equals a. 0 b.20 c.28