Answer:
18°
Explanation:
sum the parts of the ratio, 1 + 4 + 5 = 10 parts
The sum of the 3 angles in a triangle = 180° , then
180° ÷ 10 = 18° ← value of 1 part of the ratio
Since 1 is the smallest part of the ratio it represents the smallest angle, thus
smallest angle = 18°