If you do the square root of 16, you get 4 (4*4=16), so this is rational If you do the square root of 9, you get 3 (3*3=9), so this is rational If you do the square root of 49, you get 7 (7*7=49), so this is rational If you do the square root of 2, you get 1.4142....., so this is irrational, since it keeps on repeating So your answer is B. sq rt 2 Hope this helps!