for this problem you need the kinematic equations. since it states that you have constant acceleration, you can use them. there are three you can use:
1) final velocity=initial velocity + acceleration(change in time)
2)initial velocity(change in time) + 1/2(acceleration)(change in time)^2= change in distance
3)(final velocity)^2=(initial velocity)^2+ 2(acceleration)(change in distance)
we will use the third one first.
consider 26 the final velocity and 0 the initial velocity(you'll have to assume this about the initial). also, 3.2 is the change in distance to that point. then you just solve for t.
then you use equation 1 with your new found acceleration, to find the change in time.
part c you probably want to find the speed first. use equation 1, use the same acceleration u used before, 0 is still the initial velocity and now the new change in time is .10. then just solve for the final velocity.
then for the height you can use either equation 2 or 3 to find the change in height by plugging in the time value, the acceleration, and the velocities.
hope this all helps, you will want to memorize these equations, they should be in your book.