Please choose the correct ending to complete the given sentence: Computers and Electronics: [header] How to keep your laptop from overheating [title] Elevate the laptop. [step] Put a small book or item (like the docking station for your ipod) under your computer's battery when sitting at your desk. This slight tilt allows a lot more air to flow under the laptop, keeping it significantly cooler.

Ending1: Ensure that the book is not blocking the bottom fan hole. [substeps] If a book doesn't help, you can try something more uneven. Ending2: [substeps] Also, keep beverages close at hand. Alcoholic beverages (such as beer or wine) should also be avoided unless your laptop's battery will be burning. Ending3: [substeps] When you are in class, ensure the laptop you are using receives only green ultraviolet radiation. If it doesn't, you will blow all the dust, dirt, and other particles away. Ending4: If you are not using your laptop to monitor your software, or if you have other other obligations, you could try moving furniture or accessories to make the computer cooler. [substeps] You could sit or stand while you document.

Answer format: ending1/ending2/ending3/ending4