$6\mathrm{.}15.$ Complete the following input$/$output report. What is the actual backlog at the end of period $5?$

period: $12345$ total

Planned input: $78,78,78,78,78$

Actual Input: $84,80,78,82,80$

Cumulative Variance:

Planned Output: $80,80,80,80,80$

Actual Output: $85,83,76,82,84$

Cumulative Variance:

Planned backlog: $45$

Actual Backlog: $45$