Please i want to finish my homework aspnd sleep my eyes ree and im tired

Answer:
4 dots each time.
Step-by-step explanation:
Check. Bolded are the numbers given. Note that there are broken pieces that must be filled in:
5 + 4 = 9
9 + 4 = 13
13 + 4 = 17
17 + 4 = 21
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