Multiply -210 by -1.

  Multiply 54 by -1.

    Multiply -8 by -1.

    Multiply -190 by -1.

   Multiply 15 by -1.

     Multiply 10 by -1.

   Multiply 47 by -1.

   Multiply -36 by -1.

   Multiply -20 by -1.

  Multiply 23 by -1.