In the given scenario, it is most likely that the installation of rafters is an activity that , the installation of rafters is an activity which is not on the critical path
Explanation:
From the above question we know that Liam is the manager of the operations in a company which is related to a construction. Therefore in a company which deals with construction,they need the products required for construction to be delivered on a timely manner , but in this scenario, the shipment got delayed and since the delay of the shipment does not affect the deadline of the project Liam is not worried about the delay . So, it is clear that the installation of the rafters is an activity that is not on the Critical Path