You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.

Q: Question: In an office, 20 percent of the workers have at least 5 years of service, and a total of 16 workers have at least 10 years of service. If 90 percent of the workers have fewer than 10 years of service, how many of the workers have at least 5 but fewer than 10 years of service?

 Option A:  32

 Option B:  64

 Option C:  50

 Option D:  144

 Option E:  160

A: Option A
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Q: Question: A die is rolled twice. What is the probability of getting a sum equal to 9?

 Option A: 2/3

 Option B: 2/9

 Option C: 1/3

 Option D: 1/9

 Option E: 1/10

A: Option D
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Q: Question: If 50% of the 880 students at a certain college are enrolled in biology classes, how many students at the college are NOT enrolled in a biology class?

 Option A: 560

 Option B: 540

 Option C: 520

 Option D: 440

 Option E: 500

A:
Option D
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