activity cost and activity base data by product are provided below.

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

a$.$ $$18\mathrm{.}94$ per purchase order

b$.$ $$66\mathrm{.}26$ per purchase order

c$.$ $$175\mathrm{.}72$ per purchase order

d$.$ $$276\mathrm{.}26$ per purchase order