Minimum No of Non-coplanar vector whose resultant is zero is

Assertion: The minimum number of non-coplanar Vectors whose sum can be zero, is four Reason: The resultant of two vectors of unequal magnitude can be zero.

Minimum number of two coplanar vectors of equal magnitude whose vectors sum could be zero, is:

How many minimum numbers of a coplanar vector having different magntidues can be added to give zero resultant

If bar(a),bar(b),bar(c) are non-zero, non -coplanar vectors, then show that the vectors 2bar(a)-5bar(b)+2bar(c),bar(a)+5bar(b)-6bar(c)and3bar(a)-4bar(c) are coplanar.

If veca, vecb, vecc , be three on zero non coplanar vectors estabish a linear relation between the vectors: 7vec+6vecc, veca+vecb+vec, 2veca-vecb+vecc, vec-vecb-vecc

Is it possible to get zero vector as a resultant of three non-coplanar vectors ? Is the same possible in case of four non-coplanar vectors?

If a,b and c be any three non-zero and non-coplanar vectors, then any vector r is equal to where, x=([rbc])/([abc]),y=([rca])/([abc]),z=([rab])/([abc])