97.
The angle θ between the lines having slope m1 and m2 is given by
tan θ = (m2−m1)/(1+m1*m2)
y=x -> slope m1=1
y=sqrt(3)x-> slope m2=sqrt(3)
tan θ = (sqrt(3)-1)/(1+1*sqrt(3))
tan θ = (sqrt(3)-1)/(1+sqrt(3)) ......rationalize
tan θ = 2 - sqrt(3)
θ =tan^-1(2 - sqrt(3))
θ =π/12 (result in radians)
θ =15°
