Cycle time is $80s\frac{ec}{?}$ unit

All times are in seconds in the precedence diagram.

In this precedence diagram the total task time is $210sec.$

Workstation #$1$ is BC

Workstation #$2$ is AD

Which of the following statements is TRUE?

Workstation #$1$ is NOT valid because it breaks the cycle time rule

Workstation #$2$ is NOT valid because it breaks the cycle time rule

NOT valid because it breaks the precedence rule