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.
Unless there are a lot of fog in the atmosphere which can refract the beam, laser usually travel very far since the beam is formed by parallel streams of lights, unlike other light source which are more scatter. Basically, the more scattered the light is, the shorter the distant. But laser is concentrate.