The danger nowadays is that all this info is available on a video channel in many aircraft so a smart alec could ask the question and triumpnantly point out the error of the response.
Way back in the dawn of time before PA we used to compose a bulletin with the essential data on it to be passed back through the cabin.
This was often pre-written. After the bulletin had gone with our planned cruise level of 9000' (pre-pressurisation) ATC advised 9000 was not available and asked us to level at 7000'. Shortly afterwards the steward came back to say a lady was finding it difficult to breathe at 9000'. "OK," I said, "tell her we will descend to 7000'"
A few minutes later the steward came back to report, "She finds that much more comfortable!".