Please choose the correct ending to complete the given sentence: Computers and Electronics: [header] How to clean a mac keyboard [title] Shut down your laptop. [step] If your keyboard is part of your laptop, shut down the laptop before you begin cleaning. This will help prevent damage from occurring during the cleaning process.

Ending1: [substeps] Remove all of the knobs and ports that cover the computer's screen. Remove any buttons, connectors, or other startup components that appear to be hiding under your keyboard. Ending2: [substeps] If the interior of your keyboard faces down as you work, this can help lessen the vibration effect of the scrubbers. If the interior of your keyboard faces up, this will help lessen any noise. Ending3: [title] Open the device compartment and remove the plug in coaxial cables. [step] This will help you replace your main lead panel and in turn free any other hardware. Ending4: [title] Unplug your keyboard from its power source. [step] If the keyboard is part of your laptop, unplug the laptop entirely.

Answer format: ending1/ending2/ending3/ending4