1pt Steven wanted to know which of his new rocks in his rock collection contain iron. How can he determine this through chemical weathering?
O A. Place the rocks in a vacuum sealed environment.
O B. Put the rocks in acid and see how quickly they break down.
O C. Lay the rocks together outside and see if they rust.
OD. Break off a piece of each rock and observe the pieces under a microscope.

An object with initial temperature 130 ∘ f is submerged in large tank of water whose temperature is 50 ∘ f . find a formula for f ( t ) , the temperature of the object after t minutes, if the cooling constant is k = − 0.2 . remember newton's law of cooling (the rate of change of temperature with respect to time is equal to k times the difference between the temperature of the object and the surrounding temperature) ! : )