When a certain radioactive element decays, the amount, in milligrams, that remains after t years can be approximated by the function A above. Approximately how many years would it take for an initial amount of 800 milligrams of this element to decay to 400 milligrams? a. 173
b. 347
c. 693
d. 1,386
e. 2,772

Which of the following is the result of expanding

The position of a moving particle is given by the position function: f(t)=-9t-t^2-0.2t^3+0.1t^4 0 a. at what time does the particle reverse direction? b. when is the displacement positive? (round one decimal place and answer in interval notation) c. when is the displacement negative? (round one decimal place and answer in interval notation) d. when is the particle’s acceleration positive? (round one decimal place and answer in interval notation) e. when is the particle’s acceleration negative? (round one decimal place and answer in interval notation)

Maurice has 54 fewer comic books than rebecca. they have 130 comic books together .how many comic books are in maurices collection ? how many comic books are in rebeccas collection