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65% of students in your school participate in at least one after school activity. if there are 980 students in you school, how many do not participate in an after school activity?

When 142 is added to a number the result is 64 more times the number my options are 35 37 39 41

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 = 4πr^2. write your answer in scientific notation.