What Am i doing wrong?

1. The problem statement, all variables and given/known data



Find Beta of <60,-50,40>



2. Relevant equations



Cosine β = Ay/lAl





3. The attempt at a solution



lAl = 87.74964387



So its arccos(-50/87.75) = 124.62



express to 2 significant figures and it keeps telling me im wrong. I rounded to 125. kept at 124.62.. etc.

Attached Images

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