please answer clearly for an Alevel student

5. For each of these propositions, decide whether it is true. If the proposition is true, prove it. If the proposition is not true, find a counter-example. (a) The sum of two primes is prime. (b) The sum of two primes is never prime. 6. For each of these propositions decide whether it is true. If the proposition is true, prove it. If the proposition is not true find a counter-example. a) Vx2 + y2 = x+y b) For any real numbers, x and y, x2 + y2 2 2xy