Answer:
Step-by-step explanation:
From the above explanation;
The main purpose of the objective lenses is to bring together the light from the specimen and then makes it appear larger by projecting it in the body tube.
Also, the coarse adjustment knob which can be found at the arm of the microscope is usually being used to transport the specimen into focus.
The eyepiece is an opening where the viewer perceives or observe the specimen. It comprises of 10X or 15X power lens.
So; since one of the objective lenses is missing, the coarse adjustment knob not working and the eyepiece lens is also broken. It is advisable to switch to the low power of about 10X and use a fine adjustment knob for the image focus.