
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
Let sets $A=\{x\mid -2\le x\le 5\}$ and $B=\{x\mid m+1\le x\le 2m-1\}$,
1. If $m=4$, find $A\cup B$;
2. If $B \subseteq A$, find the range of the real number $m$.

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