"Expand the brackets and Simplify"
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Select all the correct answers. what is 221,000,000,000,000,000,000 expressed in scientific notation?

Mexico city, mexico, is the world's second largest metropolis and is also one of its fastest-growing cities with a projected growth rate of 3.2% per year. its population in 1991 was 20,899,000 people. use the formula p = 20.899e0.032t to predict its population p in millions with t equal to the number of years after 1991. what is the predicted population to the nearest thousand of mexico city for the year 2010?

Which ordered pair (c, d) is a solution to the given system of linear equations- c+2d=13 -9c-4d=-15