Answer:
(a) (a · b) · c has Meaningless because it is the dot product of two scalars.
(b) (a · b)c has Meaningful because it is a scalar multiple of a scalar and a vector .
(c) |a|(b · c) has Meaningful because it is the product of two scalars .
(d) a · (b + c) has Meaningful because it is the dot product of two vectors .
(e) a · b + c has Meaningless because it is the sum of a scalar and a vector.
(f) |a| · (b + c) has Meaningless because it is the dot product of a scalar and a vector .
So 8*3=24, so multiply all of the sides by 3,
the other 2 are 30 and 36
i would say D) 12 is your answer