State, in each case, whether true or false:
(i) √? + √? = √?
(ii) ?√? + ? = ?
(iii) ?√? − ?√? = √?
(iv) 2/7 is an irrational number.
(v) 5/11 is a rational number.
(vi) All rational numbers are real numbers.
(vii) All real numbers are rational numbers.
(viii) Some real numbers are rational numbers.