## problem statement

Calculate the volume of the tetrahedron with vertices at points $A_{1}, A_{2}, A_{3}, A_{4_{\text {and }}}$ its height dropped from vertex $A_{4 \text { to the face }} A_{1} A_{2} A_{3}$.

$A_{1}(4 ;-1 ; 3)$

$A_{2}(-2 ; 1 ; 0)$

$A_{3}(0 ;-5 ; 1)$

$A_{4}(3 ; 2 ;-6)$