
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
A tractor has $50L$ of oil in the tank before starting work. After starting work, it consumes $8L$ of oil per hour.  
$(1)$ Write down the functional relationship between the remaining oil $W\left(L\right)$ in the tank and the working time $t\left(h\right)$.  
$(2)$ After working for $4$ hours, how many liters of oil are left in the tank?

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