Question: Use truth tables to verify that each of the following is a logical implication.

a) \([(p\to q)\uparrow (q\to r)]\to (p\to r)\)

b) \([(p\to q)\wedge \neg q]\to \neg p\)

c) \([(p\vee q)\wedge \neg p]\to q\)

d) \(t=[(p\to r)\wedge (q\to r)]\to [(p\vee q)\to r]\)