Using rational approximations, what statement is true?

Question

81−−√<9
start root 81 end root less than 9

71−−√>61−−√
start root 71 end root greater than start root 61 end root

81−−√>9
start root 81 end root greater than 9

71 −−−√<61−−√

Answer 1

start root 71 end root less than start root 61 end root