What is the domain of the relation

Aregression was run to determine if there is a relationship between hours of tv watched per day (x) and number of situps a person can do (y). the results of the regression were: y=ax+b a=-0.662 b=30.418 r2=0.703921 r=-0.839

What is the square root of 45? (step by step working plz)

What is the 17th term in the arithmetic sequence in which a6 is 101 and a9 is 83