See the attached figure to understand the problem
we know that
tan 42°=1950/BO---------> BO=1950/tan 42°-------> BO=2165.69 ft
tan 39.5°=1950/AO---------> AO=1950/tan 39.5°-------> AO=2365.54 ft
AB=AO-BO--------> AB=2365.54 ft-2165.69 ft-------> AB=199.85 ft
the answer is
The runners are 199.85 feet apart
we know that
tan 42°=1950/BO---------> BO=1950/tan 42°-------> BO=2165.69 ft
tan 39.5°=1950/AO---------> AO=1950/tan 39.5°-------> AO=2365.54 ft
AB=AO-BO--------> AB=2365.54 ft-2165.69 ft-------> AB=199.85 ft
the answer is
The runners are 199.85 feet apart