In a $\triangle A B C$, if $r_1=2 r_2=3 r_3$, then $\sin A: \sin B: \sin C=$

In $\triangle A B C$, if $B=90^{\circ}$, then $2(r+R)=$

In a $\triangle A B C$, if $(a-b)(s-c)=(b-c)(s-a)$, then $r_1+r_3=$

In $\triangle ABC$, $\cos A + \cos B + \cos C = $