Answer:
C. 6 hours
Explanation:
So we have the ratio of 15 pages to 2 hours. To find how long it will take him to read 45 pages, divide 45 by 15 to find what 15 was multiplied by. 
45/15 = 3. 
Because the answer is 3, multiply the 2 hours by 3 as well. 
2 x 3 = 6. 
Therefore, it will take Don 6 hours to read 45 pages. 
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