A manager checked production records and found that a worker produced $210$ units while working $50$ hours. In the previous week, the same worker produced $156$ units while working $40$ hours.

a$.$ Compute Current period productivity and Previous period productivity.

Note: Round your answers to $2$ decimal places.

$\backslash$table$[[$Current period productivity,Units per hour$],[$Previous period productivity,Units per hour$]]$

b$.$ Did the worker's productivity increase, decrease, or remain the same? Note; Round your intermediate calculations and final answer to $2$ decimal places.

Worker's productivity