Which of the following is a requirement following a delay that lasts longer than 15 days?

The requirement that follows a delay lasting longer than 15 days is that the contractor must submit a claim in writing. This process is important as it formally documents the specifics of the delay, including the reasons and any impacts on the project timeline and costs. A written claim helps both parties to clarify their positions and fosters communication regarding the resolution of the issue. This requirement ensures that all delays are properly recorded and potentially provides the contractor an opportunity to receive compensation or an extension of time due to circumstances that may have been beyond their control.

The other options may not accurately reflect standard practices or requirements in the event of a delay. For instance, redirecting the contractor's efforts is not a mandated requirement in response to delays; it may or may not be necessary depending on the circumstances. Similarly, rescheduling all work may not be practical or realistic in every situation, and the need to cover the contractor's daily costs would depend on the specifics of the contract and the nature of the delay. Each of these aspects must be evaluated on a case-by-case basis rather than being a blanket requirement following a delay.