Answer: B. √25 + 1.75.
Step-by-step explanation: Rational Numbers are numbers that terminate or don't need to be terminated. For example, 1/3 is a repeating number, but we can terminate the value, whereas pi is never ending, and there is no terminating with that value. Numbers like 5.56 and 7/8 are rational because they don't need to be terminated to be rational. √25 is 5, no decimals to terminate or anything, and that makes the value rational. 1.75 is also rational, and that's why equation c is fully rational. √3 and √2 can't terminate, because both are 1.73205080757 and 1.41421356237, which means that they still can't terminate. Pi cannot terminate, so that's why the answer choices with pi aren't rational.
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