81 (degrees)

To see 81 degrees from different powers of 10:

1) Temperature  (10⁺²)
81 degrees Fahrenheit = 27.2 degrees Celsius

2) Global location (10⁺⁷)
81 degrees longitude (vertical line) = 81 degrees west of the Prime Meridian (Greenwich, England)

3) Weather (10⁺⁴)
The dewpoint is always the same as the temperature or lower. During a heat wave in a humid climate, the dewpoint can climb to over 80 degrees and the air will feel start to feel thick and heavy.

4) Angle (10⁺²)
There are 360 degrees are in a circle. Since 81 degrees is less than 90 degrees, it is an acute angle.