(i) The negation of statement p is as follows
There exists a positive real number x such that x−1 is not positive
(ii) The negation of statement q is as follows
There exists a cat that does not scratch
(iii) The negation of statement r is as follows
There exists a real number x such that neither x>1 nor x<1
(iv) The negation of statement s is as follows
There does not exist a number x such that 0<x<1