Final answer:
Using the kinematic equation for constant acceleration, Stella's velocity after 2 seconds is calculated to be 4.2 m/s.
Step-by-step explanation:
To calculate Stella's velocity after 2 seconds given her acceleration, we can use the kinematic equation v = u + at, where v is the final velocity, u is the initial velocity (which is 0 m/s assuming she starts from rest), a is the acceleration, and t is the time. Plugging in the values:
- u = 0 m/s (since she starts from rest)
- a = 2.1 m/s2
- t = 2 s
We get:
v = 0 m/s + (2.1 m/s2 × 2 s) = 4.2 m/s
Therefore, Stella's velocity after 2 seconds is 4.2 m/s.