Answer: The measure of angle A is 77.32°.
Step-by-step explanation: We are given to find the measure of angle A from the figure provided.
From the figure, we can note that
ΔABC is a right-angled triangle, where
∠B = 90°, AB = 18 units , BC = 80 units and hypotenuse AC = 82 units.
Therefore, from the laws of ratios of trigonometry we have

Thus, the measure of angle A is 77.32°.