We are given points (30,4) , (60,8) and (90,12)
To calculate the rate per minute at which the air freshener dispenses sprays,
we can use two points to find slope.
The formula for slope is given by :
let us use two points (60,8) and (90,12) to find the slope,
Slope = 4/30
So the rate per minute at which the air freshener dispenses sprays is 4/30.
So first option is correct answer .