Scientific notations, units, and rates: the united states directly emits about 5.5x1012 kg of co2 per year. the us population is 3.2x108 people. (information source: http: // a) what is the "per capita" (per person) emission of co2 per year? give the answer in scientific notation and include the units in your answer. b) change the units of the answer to part (a) to tons of co2 per decade per person. the relevant conversions are: i. 1 ton = 1000 kg ii. 1 decade = 10 years c) the number given above, is a "rate." that is, how quickly something is being produced, used, etc. in this case, it is how quickly co2 is emitted into the atmosphere. rates are generally a quantity (in this case, kg of co2), divided by an amount of time in this case, years) quantity rate =- time it's easy to calculate the rate when the equation is in this form. just divide quantity by time. but what if we already know the rate, and we want to calculate the amount of time it takes to produce (or consume) a certain quantity? we'll want to arrange the equation so that the desired value is by itself on one side of the equation (and not on the bottom of a fraction). try to rearrange the equation so that time is by itself on one side of the equation. remember that both sides will remain equal to each other *if* you to the same thing to both sides (for example, if you multiply both sides by time). world population (billions) 10,000 5000 1000 1000 1 1000 1500 1800 1900 1950 21+ b. c.e. c. e. year 2. reading charts/graphs, and rates: a) from the chart above, what is the approximate population of the world in 1950? in 2000? b) how many more people were living in 2000 than in 1950? c) how much time elapsed between 1950 and 2000? d) now, you have the "quantity" (the increase in the number of people), and an amount of time (the amount of time it took to increase by that amount. use the equation from problem #1 to determine the rate of population increase between 1950 and 2000 (in units of persons per year). e) there are 3.9x107 people in california. at the rate calculated in part c), how long would it take for the world to add the equivalent of another california (3.9x107 people)? give your answer in years. f) convert your answer to months.