Task A description:

Task A involves pouring $192m^3$ of concrete for abutments.

A concrete pump with a production rate of $15\frac{m^3}{h}r$ is used.

A crew of $2$ concreters is assigned for vibrating the concrete when it's being poured. A concreter's productivity rate is $4\frac{m^3}{m}an-$hr$.$