For each statement, state whether it is true or false. If it is false, explain briefly why it is false.

a)To compare two treatments, a paired design is more effective than an unpaired design.

b)In a randomized block design, the number of treatments must be equal to or less than the number of blocks.

c)We can use the half-normal plot to assess the significance of factorial effects whenever we do not have an estimate of variance a²

d)For a Resolution III design, all main effects are aliased with one or more two-factor interactions.