Solve for X.
Need to show the work.
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Maria walks a round trip of 0.75 mile to school every day.how many miles will she walk in 4.5 days

At store a, erasers are sold individually. the cost y of x erasers is represented by the equation y=0.75x. the costs of erasers at store b are shown in the graph.

The diameter of the moon is about 3500 km. approximate the surface area of the moon using the formula for the surface area of a sphere, s = 4? r^2. write your answer in scientific notation.