Answer:
[tex]\sin A =\frac{4}{5}[/tex]
Step-by-step explanation:
Recall the mnemonics SOH CAH TOA.
SOH means the Sine ratio is Opposite over Hypotenuse.
This implies that;
[tex]\sin A =\frac{Opposite}{Hypotenuse}[/tex]
The side opposite to angle A is 4cm and the hypotenuse is 5cm.
[tex]\therefore \sin A =\frac{4}{5}[/tex]