What is a 4-40 for?

Do closely spaced contour lines indicate a steep slope? What did the upper class in 1750 do for entertainment in 1750? What does IQ score of 56 mean? How many hours does 3 days have? Can you name all the polygons? We are both in simplest form. The product of each of your numerators and denominator is 120. Each of our numerators is a prime number. who are we? What is 4 m squared? How many inches in 45 cms? Is 487 even? What is marbles made out of? What is the chance of a couple having 5 daughters in a row? Convert 154cm into feet and inches? What is the average power consumption of 1 hp air conditioner per hour? What are the sum of all the even numbers less than 30? How do you calculate density from depth? What does UDTQCSSOND stand for? How many handshakes if 49 people shake hands with every other person in room? Which type of graph is best suited for graphing the cost of a computer versus its speed? What is greater 3 over 4 or 13 over 15? Is it true that two lines that lie in different parallel planes must be skew lines?