4: 4, 8, 12, 16, 20
7: 7, 14, 21, 28, 35
9: 9, 18, 27, 36, 45
12: 12, 24, 36, 48, 60
<span>Critical points are where the derivative is 0, i.e. where it crosses the x - axis
The Critical points lies where the derivative is 0, while it crosses the x-axis, SO, in this case the choice 3 looks like best answer for this.
</span>
You would say no because more people said yes for an annual check up
one column should be added first
