Domingo Corporation uses the weighted$-$average method in its process costing system. This month, the beginning inventory in the first processing department consisted of $400$ units. The costs and percentage completion of these units in beginning inventory were:

Cost Percent Complete

Materials costs $ $5,50050\%$

Conversion costs $ $1,70020\%$

A total of $6,800$ units were started and $6,100$ units were transferred to the second processing department during the month. The following costs were incurred in the first processing department during the month:

Cost

Materials costs $ $158,700$

Conversion costs $ $120,400$

The ending inventory was $85\%$ complete with respect to materials and $75\%$ complete with respect to conversion costs.

How many units are in ending work in process inventory in the first processing department at the end of the month?

Multiple Choice

$700$

$900$

$6,400$

$1,100$