base data by product are provided below.

The activity rate $($rounded to the nearest cent$)$ for the procurement activity cost pool is

a$.$ $$168\mathrm{.}66$ per purchase order

b$.$ $$20\mathrm{.}98$ per purchase order

c$.$ $$64\mathrm{.}38$ per purchase order

d$.$ $$315\mathrm{.}30$ per purchase order