(I'm only posting the questions I couldn't figure out, don't worry.)

An object released from rest at time t=0 slides down a frictionless incline a distance of 1 meter during the first second. The distance traveled by the object during the time interval from t=1 second to t=2 seconds is...

1 answer

Its average speed is distance over time, or 1 m/s. Since its initial speed is zero, its final speed vf1 is 2m/s to get that average.

Now, the acceleration:
a=changevelocity/time. Compute acceleration.

Now, assume that acceleration is constant.

distance1to2= distanceattime2-distanceattime1
= 2m/s*1sec+1/2 a*2^2 - (1/2 a*1^2)