Tautology And Contradiction

The proposition p rarr ~(p^^q)" is "a tautology contradiction. neither tautology nor contradiction. none of these

If statements t and f represent a tautology and a contradiction (fallacy) respectively, then p^^tequiv

If statements t and f represent a tautology and a contradiction (fallacy) respectively, then pvvf equiv

If statements t and f represent a tautology and a contradiction (fallacy) respectively, then pvvtequiv

If statements t and f represent a tautology and a contradiction (fallacy) respectively, then p^^fequiv

If statements t and f represent a tautology and a contradiction (fallacy) respectively, then p^^~pequiv

If p is any statement,t and c are a tautology and a contradiction respectively then which of the following is not correct- (a) p^^t=p(b)p^^c=c(c)p vv t=c(d)p vv c=p