Answer:
53°
Step-by-step explanation:
Hypotenuse is the longest side and it is opposite to angle 90°
[tex]\sf Sin \ B = \dfrac{Opposite \ side \ of \ angle \ B}{hypotenuse}\\\\[/tex]
[tex]= \dfrac{4}{5}\\\\=0.8[/tex]
[tex]B = Sin^{-1} \ (0.8)\\[/tex]
B = 53°
