Consider the following process:

Activity $1$

There are five activities $(1,2,3,4,5)$ and seven resources $($A$,$B$,$C$,$D$,$E$,$F$,$G$).$ Activity $1$ is performed by resources A and $B$ in parallel; activities $2$ and $3$ are performed by resources $C$ and $D,$ respectively; activity $4$ is performed by resources $E$ and $F$ in parallel, and activity $5$ is performed by resource $G.$

We know that each resource takes $12$ seconds to complete Activity $1,5$ seconds to complete activity $2,20$ seconds to complete activity $3,30$ seconds to complete activity $4,$ and $5$ seconds to complete activity $5.$

Consider the following process:

Activity $1$

There are five activities $(1,2,3,4,5)$ and seven resources $($A$,$B$,$C$,$D$,$E$,$F$,$G$).$ Activity $1$ is performed by resources A and $B$ in parallel; activities $2$ and $3$ are performed by resources $C$ and $D,$ respectively; activity $4$ is performed by resources $E$ and $F$ in parallel, and activity $5$ is performed by resource $G.$

We know that each resource takes $12$ seconds to complete Activity $1,5$ seconds to complete activity $2,20$ seconds to complete activity $3,30$ seconds to complete activity $4,$ and $5$ seconds to complete activity $5.$