1 Place the cotton balls in areas where mice are likely to enter your house, by doorways or heat vents, etc. 2  Another helpful deterrent is to grow peppermint plants near the entryways. 3  You can use the mint in cooking as well as it serving a deterrent purpose.
Nov 12, 2015. 20 kilometers (12 miles) for a 1 milliwatt beam. Laser light can travel 20 kilometers (12 miles) per-milliwatt that is contained within the laser.
We turn it on, and a beam of light comes out. The beam of light is traveling at the speed of light, nearly 300,000,000 m/s. Now, let's assume we're in a spaceship which is somehow traveling at 200,000,000 m/s. Someone outside the spaceship shines a beam of light past us.