Can yall sub to meh yt chan. nel ill sub to yall also

What is the greatest common factor of 6a, 8a^{2}, and 14?

[10 points, algebra 2]according to my answer key the restrictions are -1 and 4. but why not positive 1?

At the beginning of 1974/75,2 years a man invested #2000 in a bank at 12.5% compound interest, if it degree #650 at the end of each two years to pay his son's school fees, after payment of interest to pay his son's school fees, how much did he have left at the beginning of the 1978/79 school year?