A different car in the next lane accelerates from rest to 30 m/s at a rate of 6 m/s^2 for 5 seconds. How far does this car travel during this period?

You can use equation 4 for this:
[tex]\left(30\,\dfrac{\mathrm m}{\mathrm s}\right)^2=0^2+2\left(6\,\dfrac{\mathrm m}{\mathrm s^2}\right)\Delta x[/tex]
[tex]\implies\Delta x=75\,\mathrm m[/tex]