Americans are more conscious of the need for fitness. They have become active sports enthusiasts and more interested in good nutrition; they are aware of the need to reduce stress.

Correct

Explanation:

According to a different source, this sentence has to be corrected if it is an example of a fused sentence or a comma splice. In this example, this sentence is correct. The sentence contains several independent clauses. However, these are separated either by a period or by a semicolon. These are both correct ways to separate such sentences.

right angles are formed by perpendicular lines. if the lines would extend, to make two intersecting lines, they would form four right angles.