True or False

  1. The ratio of two real numbers is never zero.
  2. The difference of two real numbers is always a real number.
  3. The sum of two real numbers is always a real number.
  4. The quotient of two real numbers is always a real number (provided the denominator is non-zero).
  5. The quotient of two real numbers is always a rational number (provided the denominator is non-zero).
  6. The product of two real numbers is always a real number.
  7. The difference of two real numbers is always an irrational number.