Which of the following statements about the Arbitrage Pricing Theory $($APT$)$ are correct? Check all that apply.

The APT is a single$-$factor model.

The APT assumes that all investors hold the market portfolio.

The APT allows the required return be a function of two, three, four, or more factors.

The APT requires fewer assumptions than the Capital Asset Pricing Model $($CAPM$).$

Julian, an analyst at Avangard Electric $($AE$),$ models the company's stock assuming that all stocks' returns depend on only three risk factors: inflation, industrial production, and the aggregate degree of risk aversion. The risk$-$free rate is $r_{RF}=8\%,$ the return on the market is $r_M=10\%,$ and the rest of the available data is given in the following table:

$\backslash$table$[[$Variable$,$Value$],[$The required rate of return on an inflation portfolio, $r_1,8\%$