Lake Charles Seafood makes $550$ wooden packing boxes for fresh seafood per day, working in two $10-$hour shifts. Due to increased demand, plant managers have decided to operate three $8-$hour shifts per day instead. The plant is now able to produce $700$ boxes per day.

a$)$ Before the change in work rules, the company's productivity per day $=27\mathrm{.}5$ boxes$/$hour $($round your response to two decimal places$).$

After the change, the new productivity level per day $=$ boxes$/$hour $($round your response to two decimal places$).$

b$)$ Based on the changes made, the percent increase in productivity $=,\%($enter your response as a percentage rounded to two decimal places$).$