Please state your opinion in respect of the following statements, with a brief explanation.

1. "A contract must always be in writing in order to be valid and enforceable at law, even if the elements of a contract are present." Is this statement correct?
2. "For a contract to be binding at law, there MUST be consideration in cash only, and it does not matter WHEN the consideration was promised."
3. "If I picked up an item from the shelves of a supermarket, I would have accepted the store owner's offer to sell that item to me at the price on the price tag."
4. "When a husband offers a job to his wife, there can never be a binding contract between them ever because of their marital relationship."
5. "A newspaper advertisement can never be an offer."