What number does the prefix kilo- represent?

Rose drew a regression line for this paired data set. her line passed through (1, 2) and (3, 5) . what is the equation of rose's regression line?

X-intercept=-5 y-intercept=2 the equation of the line is

Sanya noticed that the temperature was falling at a steady rate of 1.4 degrees every hour from the time that she first checked her outdoor thermometer. by 6 a.m., the temperature had fallen 21 degrees. which expression can you use to find how many hours earlier she had first checked the thermometer?