IBC previously employed $1500$ workers for $10$ hours per day. The plant was able to produco $75\mathrm{.}000$ gallons in a day. As the products popularity grew the number of employees decreased$1250$ workers ot $8$ hours per day. During the sarne time investments in automation helped increase production to $125\mathrm{.}000$ gals per day. The change in their dolty labor productivity between the previous and current operation strategy is most nearly?$5$ sals$/$how$7\mathrm{.}5$ gal$/$hour$9$ gal$/$hour$12\mathrm{.}5$ gal$/$hour