There are a lot of names for it. The most common is senior slump and senioritis.
If you use a mixture of formats in a single document, it can be confusing to the reader. This is the exact opposite of what formatting is supposed to do.
Answer: c. Each line of the document has different formatting applied to it.
In the emancipation Proclamation it said that if they did not see is there 1000,000,000 by January 1 that the proclamation would go into force