National Scan, Inc., sells radio frequency inventory tags. Monthly sales for a seven$-$month period were as follows:

$\backslash$table$[[$Sales$,],[$Month$,(000)$ Units$],[$Feb$.,15],[$Mar$.,18],[$Apr$.,12],[$May$.,20],[$Jun$.,23],[$Jul$.,23],[$Aug$.,27]]$

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a$.$ Forecast September sales volume using each of the following:

$(1)$ The naive approach.

Naive approach

thousands

$(2)$ A five$-$month moving average. $($Round your answer to $2$ decimal places.$)$

Moving average

thousands

$(3)$ A weighted average using $0\mathrm{.}55$ for August, $0\mathrm{.}10$ for July, and $0\mathrm{.}35$ for June. $($Round your answer to $2$ decimal places.$)$