Gilford, Inc Only Job 105 Was Still in Process at the End

Gilford, Inc., uses a job-order costing system. Costs going through the company's work-in-process account during June are listed below. Manufacturing overhead is applied to production using a predetermined overhead rate based on direct labour cost.
\begin{array}{lr}\text { Work in Process } \\\text { Balance } & -0- & \$ 95,000 \text { Transferred out }\\\text { Direct materials } & \$ 20,000 \\\text { Direct labour } & \$ 30,000 \\\text { Manufacturing Overhead } & \$ 60,000\\\\\text { Balance } & \$ 15,000\\end{array}
Only Job 105 was still in process at the end of the month. This job had been charged with $3,000 in direct materials cost.
Required:
a.) Complete the following for Job 105:
$\begin{array}{lccc} \text { Direct materials} &\$ 3,000 \\ \text { Direct labour} & ----\\ \text { Manufacturing overhead} & ----\\ \text { Total cost at June 30} &---- \\\end{array}$

b.) Determine the total amount of materials cost charged to completed jobs during the month.