$15.$ Statement $1$:

A credit balance in the Manufacturing Overhead account at the end of the year means that manufacturing overhead was overapplied.

Statement $2$:

If the actual manufacturing overhead cost for a period exceeds the manufacturing overhead cost applied, then manufacturing overhead would be considered to be overapplied.Statement $3$:

The entire difference between the actual manufacturing overhead cost for a period and the applied manufacturing overhead cost is typically closed to the Work in Process account.