Please choose the correct ending to complete the given sentence: Home and Garden: [header] How to clean concrete countertops [title] Consult your manufacturer's guide or contractor. [step] If you installed your countertops yourself, then keep a photo of the concrete mix and surface coating so that you can consult it for reference. If you had a contractor install everything, then they more than likely gave you instructions post-installation.

Ending1: [substeps] Be skeptical about manufacturer directions for first-time installation at the bottom of your user manual, but read the instructions to create some accurate results. [title] Choose a brush for scrubbing away tarnish. Ending2: [substeps] Speak to your contractor about the strength of your backing sheet. [title] Wipe up remaining cement with a paper towel or a microfiber cloth. Ending3: If not, go ahead and call them prior to your first cleaning with any immediate questions. [substeps] Be aware that cleaning your countertops with solutions or methods outside of the approved ones may result in your warranty being voided. Ending4: [substeps] Many modern, non-commercial models have bare-wood finishes. However, unfinished surfaces cannot be cleaned by any other cleaner.

Answer format: ending1/ending2/ending3/ending4