Answer:
The answer is "tender"
Explanation:
The call for proposals is indeed a call for just a project or a structured proposal like a share sale to approve. Frameworks require the mechanism through which authorities and commercial banks request offers on large projects to also be made within such a limited time. Its tender definition can be quickly chewed but are delicate or fragile to use.
The plural form of roof is roofs.
Although there are many words where f would become v, like in hooves, this is not one of those cases.
A solid is more impenetrable
