• A light microscope uses light as its source of illumination, while an electron microscope uses a beam of electrons.

1. a)
Here are four differences between a light microscope and an electron microscope:

• A light microscope uses light as its source of illumination, while an electron microscope uses a beam of electrons.
• A light microscope uses glass lenses to focus light, whereas an electron microscope uses electromagnetic lenses to focus electrons.
• Light microscopes have lower magnification and resolution compared to electron microscopes.
• Light microscopes can view living specimens, while electron microscopes require specimens to be dead, dehydrated, and often coated in metal, viewed in a vacuum.

b)
Here are three limitations of using an electron microscope in school laboratories:

• They are very expensive to purchase and maintain, making them inaccessible for most school budgets.
• They are large and complex, requiring a dedicated space and specialized training for operation and maintenance.
• The specimen preparation process is elaborate and time-consuming, often requiring specialized equipment and skills not typically available in a school setting.

c)
i. Making rough focus: Coarse adjustment knob
ii. Reflecting light from the source: Mirror

d)
M: Eyepiece
N: Stage clip
O: Fine adjustment knob
P: Mirror