Two radar station 18.5 miles apart are tracking a plane. the angle of elevation from station a is 48 and the angle of elevation from station b is 74. how far is the plane from station b?

See the attached figure to better understand the problem

we know that

in the triangle ABC
angle C=180-(48+74)------> angle C=58° 
applying the law of sines
BC/sin 48=18.5/sin 58°------> BC=18.5*sin 48/sin 58-----> BC=16.21 miles

the answer is
16.21 miles

128/3reason being 5 and 1/3 = 16/316/3 • 2/3 = 32/31 and 1/3 = 4/3 32/3 • 4/3 this will equal 128/3