If a time series exhibits increasing seasonal variation, one approach is to first use a(n) transformation that produces

[answerhappygod]

If a time series exhibits increasing seasonal variation, one
approach is to first use a(n) transformation that produces a
transformed time series that exhibits constant seasonal variation.
Then, variables can be used to model the time series with constant
seasonal variation.
Multiple Choice
fractional power, dummy
fractional power, constant
autocorrelation, constant
autocorrelation, dummy