Which of the following about APT are true?

$1.$ Fama French three factor model $($FF$3)$ can be argued as one form of the APT model.

$2.$ Fama French three factor has two additional systematic risk relative to the CAPM. One is the beta with respect to the risk captured mainly by small stocks $($SMB$).$ The other is the beta with respect to the risk captured by value stocks $($HML$).$

$3.$ FF$3$ explains stock returns better than the CAPM. In other words, there will be on average lower alpha, higher R squared if you regress stock returns on the FF$3$ factors $($MKT$,$ HML$,$ SMB$)$ than regressing on MKT only.

$1$

$12$

$23$

$123$