They can help strengthen a point as long as the question is then enforced. They help to convince the listener since usually even thought it's not said we usually think yes in our head after hearing a rhetorical question.
Answer/Explanation:
The two correctly cited sourxes are:
1. Bravo, Susana. "Amazonian Black Howler Monkeys: Seed Dispersers or Pests?" Biotropica, vol. 40, no. 8 (2008), pp. 71–76.; and
2. Martins, Marcel. "Pollination and Pollinators of the Amazonian Forests." Global Rainforests, vol. 19, no. 5 (2015), pp. 17–28.
These two are correct because they contain the title of the work, the title of the journal, it's volume, year of publication and the page where the work is located in the journal.
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