The equation is
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This is an exponential equation, we just keep multiplying each value by 4 to get the next value.
Thus the common ratio is 4.
ii. The y-intercept is the point the graph cuts the y-axis, also the point where x = 0. Putting x = 0, into the equation, we obtain.

Thus, the y-intercept is (0, 1 )
iii. The horizontal asymptote.
The horizontal asymptote is the horizontal line the graph approaches.
Since the function is an exponential one. with zero y-intercept.
The horizontal asymptote is the line

Or the x-axis.
Therefore, The horizontal asymptote is the line y = 0