What are the domain and range of f(x)= (1/5)^x

Aflute is on sale for 20% off. including the discount and 8% tax, the sales price is $216.

Suppose you are going to graph the data in the table. minutes temperature (°c) 0 -2 1 1 2 3 3 4 4 5 5 -4 6 2 7 -3 what data should be represented on each axis, and what should the axis increments be? x-axis: minutes in increments of 1; y-axis: temperature in increments of 5 x-axis: temperature in increments of 5; y-axis: minutes in increments of 1 x-axis: minutes in increments of 1; y-axis: temperature in increments of 1 x-axis: temperature in increments of 1; y-axis: minutes in increments of 5

How many sides does a regular polygon have if each exterior angle measure is 45 degrees explain your answer, i really don't understand this.