It can be modeled by an exponential function, f(x) is divided by 3 each time x increases by 1.
This means that the base of the exponential function is 1/3, and since the value of f(x) when x=0 is 81, 
I’m guessing you meant central tendency.
I’d say the mean is the best measure for period 2. This is because it doesn’t have any extremely low or high values which could distort the mean value.
If it did ie. 8, then I would choose median as it is less affected by anomalous results
I’m sorry this is messy but I hope this is right!! <3
19.8 rounded to 1 s.f. is
20
Answer:
tell the teacher u ar at home