The angle of inclination to the nearest tenth of degree is 78.7°
Angle of inclination is also thesame as angle of elevation. To calculate this angle we use trigonometric ratios.
Trigonometric ratio is the relationship between the sides of a right triangle.
Tanx = opp/adj
where x is the acute angle
opposite side to x is the height of the pole
adjacent is the length of the shadow
Therefore;
tanx = 100/20
x = tan⁻¹ 5
x = 78.7° ( nearest tenth of degree)
Therefore, the angle of inclination to the nearest tenth of degree is 78.7°