A substance decays according to the equation y=ae^-.215t where t is the time in hours. Find the half-life of the substance.

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Ascatterplot is produced to compare the size of a school building to the number of students at that school who play an instrument. there are 12 data points, each representing a different school. the points are widely dispersed on the scatterplot without a pattern of grouping. which statement could be true

The function v(r)=4/3pir^3 can be used to find the volume of air inside a basketball given its radius. what does v(r) represent

Find cot x if sin x cot x csc x = √2