
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
An emergency braking system of a car is required to complete braking within 2 seconds in certain situations. The function of displacement (unit: m) with respect to time (unit: s) is given by $s(t)=-3t^3+t^2+20$. Calculate:
(1) The average velocity within the first second after the braking starts;
(2) The average velocity between 1 second and 2 seconds of braking;
(3) The instantaneous velocity at 1 second of braking.

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