Can someone pls show how to do this is with explanation

Caleb and emily are standing 100 yards from each other. caleb looks up at a 45° angle to see a hot air balloon. emily looks up at a 60° angle to see the same hot air balloon. approximately how far is the hot air balloon off the ground? a)44.2 yd. b)63.4 yd. c)73.2 yd. d)89.7 yd.