B. Authorization from ATC.

First, find the tower location from the coordinates provided. The latitude and longitude tick marks on the sectional chart are one minute apart, fifteen minutes per major grid. So to locate this tower you need to convert from decimal to degrees (also called DMS for Degrees, Minutes, Seconds). The degrees part doesn't change, so simply multiply the decimal part by 60 to get the DMS measurement. 46.9 * 60 = 46°,54' and 98.6 * 60 = 98°,36'. Now we plot the intersection of 46°, 54' and 98°, 36' and we can see that we are in the Jamestown airport Class E airspace. The dashed magenta line means Class E airspace starts at the surface.