What are 4 equations that equal 16

Initially 100 milligrams of a radioactive substance was present. after 6 hours the mass had decreased by 4%. if the rate of decay is proportional to the amount of the substance present at time t, find the amount remaining after 24 hours. (round your answer to one decimal place.)

Add the fractions, and simply the result to lowest terms. 2/3 + 2/7= ?

If sec theta = 5/3 and the terminal point determined by theta is in quadrant 4, then