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Convert 6 kilograms to grams.

The population of the U.S. is about 309,975,000 , covering a land area of 3,717,000 square miles. The population of India is about 1,184,639,000 , covering a land area of 1,269,000 square miles. Compare the population densities of the two countries.

The Deepwater Horizon oil spill resulted in 4.9 million barrels of oil spilling into the Gulf of Mexico. Each barrel of oil can be processed into about 19 gallons of gasoline. How many cars could this have fueled for a year? Assume an average car gets 20 miles to the gallon, and drives about 12,000 miles in a year.

The flash of lightning travels at the speed of light, which is about 186,000 miles per second. The sound of lightning (thunder) travels at the speed of sound, which is about 750 miles per hour. a. If you see a flash of lightning, then hear the thunder 4 seconds later, how far away is the lightning? b. Now let's generalize that result. Suppose it takes \(n\) seconds to hear the thunder after a flash of lightning. How far away is the lightning, in terms of \(n ?\)

Sound travels about 750 miles per hour. If you stand in a parking lot near a building and sound a horn, you will hear an echo. a. Suppose it takes about \(1 / 2\) a second to hear the echo. How far away is the building \({ }^{13}\) ? b. Now let's generalize that result. Suppose it takes \(n\) seconds to hear the echo. How far away is the building, in terms of \(n ?\)

Research or make educated estimates for any unknown quantities needed to answer the question. A restaurant in New York tiled their floor with pennies \({ }^{18}\). Just for the materials, is this more expensive than using a more traditional material like ceramic tiles? If each penny has to be laid by hand, estimate how long it would take to lay the pennies for a \(12 \mathrm{ft}\) by 10ft room. Considering material and labor costs, are pennies a cost-effective replacement for ceramic tiles?