Can someone help me with these please?

Consider the reaction 2x2y2+z2⇌2x2y2z which has a rate law of rate= k[x2y2][z2] select a possible mechanism for the reaction.

Consider the sequence below. 3 , 1 , 1/3 , 1/9 , select the explicit function which defines the sequence.

The population of a bacteria colony grows by a consistent percentage each hour and can be modeled by the function y = 500(1.16)t. what does the value 500 represent in the function?