Removing and replacing keys on Acer Aspire laptop's keyboard may require a small screwdriver for precision. Keyboard keys of Acer laptops designed for easy removal and replacement.
How to Measure Air Pollution for a Science Fair Project. Pollution is one among the major problems of todayâs world and air pollution is one root cause of many environmental issues. You can use a magnifying glass for this purpose as the dust particles are too tiny to be seen with necked eye. 2  Count the number of dust particles carefully stuck to the Vaseline in each square and note them down on a note book. 3  Use the number of dust particles sticked to the squares as a proof of air pollution.
The WHO database contains results of ambient (outdoor) air pollution monitoring from almost 1600 cities in 91 countries. Air quality in the database is represented by the annual mean concentration of particulate matter (PM10 and PM2.5, i.e. particles smaller than 10 or 2.5 micrometres).