If the points whose position vectors are 2i + j + k, 6i - j + 2k and 14i - 5j + pk are collinear then the value of p is

If the points whose position vectors are -2i + 3j + 5k, i + 2j + 3k, lambda i - k are collinear, then lambda =

The three points whose position vectors are i + 2j + 3k, 3i + 4j + 7k and -3i - 2j - 5k

The points whose position vectors are 2i + 3j + 4k, 3i + 4j + 2k and 4i + 2j + 3k are the vertices of

The three points whose position vectors are i+2j+3k, 3i+4j+7k, and -3i-2j-5k

Values of a for which the points A, B, C with position vectors 2i - j+k, i - 3j - 5k and ai - 3j +k, respectively, are the vertices of a right angled triangle with C = (pi)/2 are