1. 1. Every three times I clean my room, my mom makes me an apple pie. I cleaned my bedroom nine times. How many apple pies does she owe me? You must show every step of your problem set-up, and you must use units!

2. 2. A Centreville High School senior was applying to college and wondered how many applications she needed to send. Her counselor explained that with the excellent grade she received in her APES class, she would probably be accepted to one school out of every three to which she applied. (3 applications = 1 acceptance). She realized that for each application, she would have to write 3 essays (1 application = 3 essays), and each essay would require 2 hours worth of work (1 essay = 2 hours). As we know, writing essays is no simple matter. For each hour of serious essay writing, she would need to expend 500 calories (1 hour = 500 calories), which she could obtain by eating her mom’s apple pies (1 pie = 1000 calories). How many times would she have to clean her room in order to be accepted at 10 colleges? Hopefully you didn’t skip Problem #1.

3.  3. Title: "A Short Drive - Part 1"  Recently, it was raining pretty hard, so one of us decided to drive the one-half mile to get somewhere, rather than walk or ride a bicycle. The drive was 1 mile total, there and back, and if we assume the car gets 30 miles per gallon of gasoline, it used 1/30 (.033) of a gallon of gas.  1. If 1 billion people made this decision once a week for a year, how much gas (in gallons) would they would use?  2. How far could you drive a typical car (30 miles/gallon) on this much gas?  3. About how many typical cars could this fuel for their lifetimes (assuming a typical car gets 100,000 miles in a lifetime and uses about 3300 gallons of gas)?

4. 4.Because you never learned dimensional analysis, you have been working in a fast food restaurant for the past 35 years, wrapping hamburgers. Each hour, you wrap 184 hamburgers. You work 8 hours per day. You work 5 days a week. You get paid every 2 weeks with a salary of $840.34. How may hamburgers will you have to wrap to make your first million dollars? ( A side note: you are in a “closed loop.” If you can solve the problem, you will have learned dimensional analysis, and you can get a better job. But since then you wouldn’t be working there any longer, your solution would be wrong. If you continue to work there, that means you can’t solve the problem. So let’s overlook this “catch-22” and imagine that you can both solve the problem and continue to wrap hamburgers)

5. Homework: A Short Drive, Part 2 Although the gasoline used in a car and the fuel oil used in a home furnace are not exactly the same (gasoline is more refined, and will have a somewhat different energy content per gallon than fuel oil), for estimating purposed we will consider them to be equivalent. Assuming 2000 gallons of fuel oil can heat a house for a year, how many homes could this amount of gasoline heat for a year? In NH, there are about 1 million people that live in 300,000 homes. Virginia has 7 million people. How long would this fuel last all of the home in Virginia?

6. 5. An environmental science teacher was supplementing his summer income by working at a golf course. He found a liquid which caused him to slice ball after call in the water without bothering him at all. He thought this was an important liquid to identify, so he set out to determine its density. He found that a sample of the liquid had amass equal to 455 golf balls, and occupied a volume equal to 620 cups of water, which he obtained at the 7 th hole. Each golf ball massed 50 g, and the water cups at the 7 th hole of the golf course held 45 ml water each. What is the density of the unknown liquid?