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.
The majority of the laser pointers used in the U.S. are Class 3a diode lasers in the 630-680nm wavelength (translation: your garden-variety red laser), with a maximum output of between 1 and 5 milliwatts. Here's where it gets a little tricky.