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 sequence contains y numbers of alternating positive and negative numbers, If the first number is postive and y is an even number, how many negative numbers are in it?

Option A: (y+1

Option B: (y-1

Option C: y/(2+1

Option D: y/(2-1

Option E: y/2
Option E

Question: Which of the following is greatest?

Option A: 1/10

Option B: 1/100

Option C: 1/1000

Option D: 1/10^9

Option E: 1/5
Option E

Question: A small, rectangular park has a perimeter of 560 feet and a diagonal measurement of 400 feet. What is its area, in square feet?

Option A: 76,800

Option B: 19,600

Option C: 20,000

Option D: 20,400

Option E: 20,800
Option A