
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
Given a moving circle C: $(x-m)^2+(y-2m)^2=m^2$ ($m>0$)  
(Ⅰ) When $m=2$, find the equation of line $l$ that passes through the origin and is tangent to circle C;  
(Ⅱ) If circle C is internally tangent to circle E: $(x-3)^2+y^2=16$, find the value of the real number $m$.

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