The Sit $-$ N$-$Spin Corporation manufactures and assembles office chairs. Sit $-$ N$-$Spin uses an activity $-$ based costing system to allocate all manufacturing

conversion costs. Each chair consists of $20$ separate parts totaling $$125$ in direct materials, and requires $2\mathrm{.}0$ hours of machine time to produce. Additional

information follows:

Activity

Materials handling

Machining

Assembling

Packaging

Allocation Base

Number of parts

Machine hours

Number of parts

Number of finished units

Cost Allocation Rate

$$2\mathrm{.}75$ per part

$$3\mathrm{.}00$ per machine hour

$$1\mathrm{.}50$ per part

$$2\mathrm{.}75$ per finished unit

What is the cost of assembling per chair?

A$.$ $$5\mathrm{.}50$

B$.$ $$6\mathrm{.}00$

C$.$ $$30\mathrm{.}00$

D$.$ $$55\mathrm{.}00$