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 database contains results of urban outdoor air pollution monitoring from almost 1100 cities in 91 countries. The way air pollution is measured here is by the concentration of fine particulate matter, that is particles smaller than 10 or 2.5 microns - called PM10 and PM2.5. For each country where data is available the annual mean concentration of PM10 is given.