
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
During a certain exhibition, there was a spectacular helicopter aerobatic performance. The heights (in kilometers, with ascent as positive and descent as negative) of helicopter $A$ in the first $5$ performances after takeoff were: $+3.6$, $-2.4$, $+2.8$, $-1.5$, $+0.9$.  
$(1)$ What is the highest altitude reached by the helicopter during this performance?  
$(2)$ After completing the above $5$ performances, what is the altitude of helicopter $A$ in kilometers?  
$(3)$ If another helicopter $B$ in aerobatic flight has heights of $+3.8$, $-2$, $+4.1$, $-2.3$ in the first $4$ performances after takeoff. To make the altitude of helicopter $B$ after completing the 5th performance the same as helicopter $A$, determine whether the 5th performance of helicopter $B$ is an ascent or descent, and by how many kilometers.

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