Answer:
42 degrees
Step-by-step explanation:
To find the complement of an angle, subtract that angle from 90.
90 - 48 = 42
The y-intercept represents the initial girth of the tree. Assuming that the X-axis represents time in this scenario (as it usually does) the y-axis, therefore, represents the girth of the tree. The y-intercept is located where X = 0. So if no time has passed then this must be the first measurement of the girth of the tree.
