perl -V

  @INC:
    C:/strawberry/perl/lib
    C:/strawberry/perl/site/lib
    C:\strawberry\perl\vendor\lib
    .

require Calc; - Calc.pm somewhere in @INC

require Math::Calc; - Math/Calc.pm somewhere in @INC

require Math::Calc::Clever; - Math/Calc/Clever.pm somewhere in @INC