State whether each expression is meaningful. if not, explain why. if so, state whether it is a vector or a scalar. a. a. (bxc)i. the expression is meaningful. it is a vector. ii. the expression is meaningful. it is a scalar. iii. the expression is meaningless. the cross product is defined only for two vectors. iv. the expression is meaningless. the dot product is defined only for two vectors. b. a x (b. c)i. the expression is meaningful. it is a vector. ii. the expression is meaningful. it is a scalar. iii. the expression is meaningless. the cross product is defined only for two vectors. iv. the expression is meaningless. the dot product is defined only for two vectors. c. a x (bxc)i. the expression is meaningful. it is a vector. ii. the expression is meaningful. it is a scalar. iii. the expression is meaningless. the cross product is defined only for two vectors. iv. the expression is meaningless. the dot product is defined only for two vectors. d. (a. b). ci. the expression is meaningful. it is a vector. ii. the expression is meaningful. it is a scalar. iii. the expression is meaningless. the cross product is defined only for two vectors. iv. the expression is meaningless. the dot product is defined only for two vectors. e. (a. b)x(c. d)i. the expression is meaningful. it is a vector. ii. the expression is meaningful. it is a scalar. iv. the expression is meaningless. the cross product is defined only for two vectors. v. the expression is meaningless. the dot product is defined only for two vectors. f. (axb). (cxd)i. the expression is meaningful. it is a vector. ii. the expression is meaningful. it is a scalar. iii. the expression is meaningless. the cross product is defined only for two vectors. iv. the expression is meaningless. the dot product is defined only for two vectors.