
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
In $\triangle ABC$, it is known that $\sin \left( \frac {\pi}{2}+A \right)= \frac {11}{14}$, $\cos (\pi-B)=- \frac {1}{2}$.  
$(1)$ Find the values of $\sin A$ and $B$;  
$(2)$ If the sides opposite angles $A$, $B$, and $C$ are $a$, $b$, and $c$ respectively, and $a=5$, find the values of $b$ and $c$.

Present the answer in LaTex format: \boxed{Your answer}
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