Option A is correct.
Cathy needs to collect linear data . She should collect the data of option A-The height of a building for 20 years.
Explanation:
Linear data is that data whose slope is always same. Here lets assume, initially the building had 2 floors. Each year 2 floors are added above the previous floors. So our coordinate will be (0,2) (1,4) (2,6) (3,8) and so on.
So slope = [tex]\frac{difference in y}{difference in x}[/tex]
= [tex]\frac{4-2}{1-0} = \frac{2}{1}[/tex]
= [tex]\frac{8-6}{3-2}[/tex] = [tex]\frac{2}{1}[/tex]
So, here slope is 2 for all coordinates.
