Answer:
Fine focus.
Explanation:
If you're referencing a microscope, then it would be fine focus. Coarse focus is a basic focus used to properly see a specimen, while fine focus enhance clarity and precision. To use both, you have to gently twist a knob until you can see the specimen at a desired clarity.
Here's a reference image if you need it, it's labeled all the parts of a microscope.
 
        
             
        
        
        
Answer:
Let other scientists closely review her work
Explanation:
Ideally, experiments are carried out by scientists to find solution to an observed problem or provide answer to a scientific question. However, the outcome of experiments are not generally accepted in the world of science until they are peer-reviewed. 
Peer review is when other scientists in the same field (peers) with the scientist performing the experiment make a thorough evaluation in order to ascertain its quality as a scholarly research. Hence, in this question, the scientist could help other scientists judge the validity of her results by LETTING OTHER SCIENTISTS CLOSELY REVIEW HER WORK.