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.

Question: A man rows to a place 48 km distant and come back in 14 hours. He finds that he can row 4 km with the stream in the same time as 3 km against the stream. The rate of the stream is:

 Option A: 2 km/hr

 Option B: 1 km/hr

 Option C: 4 km/hr

 Option D: 6 km/hr

 Option E: 5 km/hr
Option B

Question: Two pipes A and B can separately fill a cistern in 10 and 15 minutes respectively. A person opens both the pipes together when the cistern should have been was full he finds the waste pipe open. He then closes the waste pipe and in another 4 minutes the cistern was full. In what time can the waste pipe empty the cistern when fill?

 Option A: 7

 Option B: 9

 Option C: 5

 Option D: 4

 Option E: 8
Option E

Question: If 4 spiders make 4 webs in 4 days, then 1 spider will make 1 web in how many days?

 Option A: 1

 Option B: 3

 Option C: 5

 Option D: 4

 Option E: 6

Option D