Answer:
19.4 (rounded to 3 significant figures)
Explanation:
SOH CAH TOA
You would use CAH for this question because you are told to find the length for BC, which is the hypotenuse and you are told the adjacent line is 6.3cm.
H=A÷C
=6.3÷cos(71)
=19.3507869666
H=19.4 (rounded to 3 significant figures)