
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
Among the following four statements:  
① The range of the function $y=0.7^{\frac{1}{x}}$ is $(0, +\infty)$;  
② If the line $2x+ay-1=0$ is parallel to the line $(a-1)x-ay-1=0$, then $a=-1$;  
③ The equation of the line that passes through point A$(1, 2)$ and has equal intercepts on the coordinate axes is $x+y=3$;  
④ If the diameter of the base and the height of a cylinder are both equal to the diameter of a sphere, then the lateral surface area of the cylinder is equal to the surface area of the sphere.  
The correct statement(s) is(are) marked by the number(s) \_\_\_\_\_\_.

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