Zulfiia Ishmukhametova / Alamy
An easy way to clean out a glass jar is to pour some water in it, screw on the lid and shake it. Is there an optimal amount of water to put in for the most effective cleaning?
Alan Baker
Swarthmore, Pennsylvania, US
Aunt Spray/Shutterstock
What would the horizon and landscape look like on a disc-shaped planet?
Gary Miller
Metamora, Michigan, US
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