How many rows does a truth table with N variables have? Show that P rightarrow Q) is equivalent to P doubleheadarrow Q Show that (P rightarrow Q) logicaland (P rightarrow Q) is equivalent to P doubleheadarrow Q Recall the following truth table for the XOR operator (also written as a. XOR is the negation of an operator you saw in class. Can you identify this operator? b. Create an expression using only NOT (), OR (v) and AND(logicaland) operators that is equivalent to XOR. Show why your expression is correct