Given three vectors U=2i^+3j^−6k^ , V=6i^+2j^+3k^ and W=3i^−6j^−2k^ which of the following hold good for the vectors U , V and W ?
(1) U , V and W are linearly dependent
(2) (U×V)×W=0
(3) U , V and W form a triplet of mutually perpendicular vectors
(4) (U×V×W)=0