Given:
Initial speed, u = 0 m/s
Final speed = 4 m/s
Time, t = 2 seconds
Given that acceleration remains the same, let's find the speed after 10 seconds.
Apply the formula:

Where:
v is the final speed
u is the initial speed
a is the acceleration
t is the time.
Hence, we have the equation:

Let's find the acceleration (a) from the equation above.
Divide both sides by 2:

The acceleration is 2 m/s^2.
After 10 seconds, given that the acceleration is the same, we have:

Let's solve for the speed v.

Therefore, the speed after 10 seconds will be 20 meters per second.
ANSWER:
B. 20 m/s