you have too sight the last name of the author and the page number whether it is a quote or paraphrased. the only time you don't have to is if you include it in the sentence.
Example for when you don't have to cite in text:
On page 13 Martin says, "blah blah bah bluh bleh blah"
... otherwise just put the citation in parentheses after the quote/paraphrase like so: (Martin,13)
Answer:
Simile, Personification
Explanation:
Simile - (whatever the lines are talking about) circling like the clouds
Personification - clouds that swim
I think it's "Pictures display information when written instructions are more complicated". Personally I believe it's just a majorly confusing way of saying: when the written instructions are too complicated they use pictures as well.
If you use credible sources, people trust you more because there is true EVIDENCE to support whatever claim there is. That makes it easier to believe and the research more reliable as it comes from facts that have been proven.