State whether each expression is meaningful. if not, explain why. if so, state whether it is a vector or a scalar. (a) a · (b × c. the expression is meaningful. it is a vector. the expression is meaningful. it is a scalar. the expression is meaningless. the cross product is defined only for two vectors.

The accompanying normal probability plot was constructed from a sample of 30 readings on tension for mesh screens behind the surface of video display tubes used in computer monitors. does it appear plausible that the tension distribution is normal? the given probability is has a significant downward curve, so it is plausible that the tension distribution is normal. the given probability is has a significant downward curve, so it is not plausible that the tension distribution is normal. the given probability is quite linear, so it is plausible that the tension distribution is normal. the given probability is has a significant upward curve, so it is not plausible that the tension distribution is normal. the given probability is quite linear, so it is not plausible that the tension distribution is normal.