Omg ! test ! explain how to focus a microscope using the high-power lens. include any safety issues you need to be aware of.

1)magnification goes by 10x (read 10 times), 100x,1000x and some goes 10,000x 

2)Always focus first using lowest power possible first, switch to medium power (100x) after it's focused on low power(10x), on 100x, use the small knob to focus it more. DO NOT touch the bigger nob when in medium or high power. Switch to high power (100x) when it is focused on medium power, again focus again using the small knob on high power. 

3) So it doesn't gather dust and fog up the lense? that one should be self explanatory