1 foot = 12 inches,
so 1 in=1/12 ft,
this means 2 in=2/12=0.1667 ft.
check the picture,
let the black line segment represent 30 ft of the roof, the blue line segment represent the gutter.
let α be the angle formed by the roof and the gutter.
tan α =(opposite side)/(adjacent side)= 0,1667/30=0.00556
then, α=arctan(0.00556)=0.39 (degrees)
the last result is found using a scientific calculator or other software.
Answer: 0.39 (degrees)