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.
But donât worry âthe technology is well established. and reliable!A laser distance meter can measure distances of up to 30m with an accuracy of Ã3mm. An Ultrasonic Distance Meter works on a similar principle, but instead of light it uses sound with a pitch too high for the. human ear to hear.