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.
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Question: Question: A is faster than B. A and B each walk 24 km. The sum of their speeds is 7 km/hr and the sum of times taken by them is 14 hours. Then, A's speed is equal to?

 Option A: 2 km/hr

 Option B: 3 km/hr

 Option C: 4 km/hr

 Option D: 7 km/hr

 Option E: 8 km/hr

Answer: Option B


Question: Question: If integers a and b are distinct factors of 30, which of the following CANNOT be a factor of 30?
I. ab + b^2
II. (a + b)^2
III. a + b

 Option A: I only

 Option B: II only

 Option C: III only

 Option D: I and II only

 Option E: I, II, and III

Answer: Option B


Question: Question: In a certain province in Italy there are 15 cities. If a single road segment connects only two cities, how many road segments are required in order to connect the cities so that each city is connected to all other cities with a single road segment?

 Option A: 30

 Option B: 105

 Option C: 330

 Option D: 14!

 Option E: 15!

Answer:
Option B