
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 school cafeteria serves 500 students every Monday, with two meal options, A and B, available for selection. Survey data indicates that of the students who choose meal A on a Monday, 20% switch to meal B the following Monday. Of those who choose meal B, 30% switch to meal A the following Monday. Let $a_n$ and $b_n$ represent the number of students selecting meals A and B, respectively, on the nth Monday. Given that $a_1=300$, calculate:  
(1) The value of $a_2$;  
(2) Whether the sequence $\{a_n - 300\}$ is constant and explain the reasoning.

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