Which of the following are true? Unless it is stated other-wise, assume that x, y, and e are real numbers.
(a) For every x, x < x + 1.
(b) There exists a natural number N such that all prime numbers are less than N. (A prime number is a natural number whose only factors are 1 and itself.)
(c) For every x > 0, there exists a y such that y > 1
(d) For every positive x, there exists a natural number n such that - 1 < x.
(e) For every positive s, there exists a natural number n such that 1/2n < ε.