ruby, 100 bytes

Result

AC

Duration

536ms

Code [DL]

require'matrix'
a,b,c,d=STDIN.lines.map{|l|Vector[*l.split.map(&:to_i)]}
p Matrix[b-a,c-a,d-a].det/6

stdin

15 45 02
48 45 73
64 07 17
73 97 60

stdout

39820

stderr

/volume/CODE:2: warning: IO#lines is deprecated; use #each_line instead

strace