Im in desperate in need of help

Use the frequency distribution, which shows the number of american voters (in millions) according to age, to find the probability that a voter chosen at random is in the 18 to 20 years old age range. ages frequency 18 to 20 5.9 21 to 24 7.7 25 to 34 20.4 35 to 44 25.1 45 to 64 54.4 65 and over 27.7 the probability that a voter chosen at random is in the 18 to 20 years old age range is nothing. (round to three decimal places as needed.)

Bring the fraction a/a-4 to a denominator of 16-a^2

Which statement best explains whether the table represents a linear or nonlinear function? input (x) output (y) 2 5 4 10 6 15 8 20 it is a linear function because the input values are increasing. it is a nonlinear function because the output values are increasing. it is a linear function because there is a constant rate of change in both the input and output. it is a nonlinear function because there is a constant rate of change in both the input and output.