angle of elevation.
On the first, the 456 is the opposite leg and the 837 is the adjacent to the angle of elevation so use tangent (from soh cah toa); x = the angle measure
tan x = 456/837
inverse tan (456/837) = x so do that on your calculator (be sure it is in degree mode).
Then for Ramsey, 1453 is opposite leg and 2960 is adjacent so you have tan x = 1453/2960 and do like the first one.