A fracture is a crack or break in the bone. Some symptoms of a fracture include swelling, tenderness, and bruising. Four common fracture types are stable, compound, transverse, and oblique.
Answer:
C
Explanation:
The main obstacle that needed to be overcome was the production of penicillin in large enough quantities. This is because the penicillin antibiotic is naturally produced by Penicillium mold, but this process takes lots of time to only produce small samples. With the enormous number of troops on the frontlines during WWII, Penicillin needed to be mass-produced quickly, which scientists figured out how by growing Penicillium mold. Doing so allowed them to create large quantities of this mold which would produce large enough batches of penicillin to be effective.
Associative learning is the process by which someone learns an association between two stimuli, or a behavior and a stimulus. The two forms of associative learning are classical and operant conditioning. (From google)