Conservation of Energy Help

1. The problem statement, all variables and given/known data
I have a homework assignment that I am stuck on using the attached table.

Problem 1: I have to find the velocity when given the mass and height.
Problem 2: Then I have to find the height when given the velocity and mass.

2. Relevant equations
P.E. = m*g*h
K.E. = 1/2*m*v^2

Mass = 1kg
Gravity = 9.8m/s

3. The attempt at a solution
P.E.(1) = 1kg * 9.8m/s * .5m
P.E.(1) = 4.9J

P.E.(2) = 1kg * 9.8m/s * .2m
P.E.(2) = 1.96J

K.E.(1) = 0m/s

K.E.(2) = 1/2*1kg*(.8m)^s
K.E.(2) = .32J

K.E.(1) + P.E.(1) = K.E.(2) + P.E.(2)
0m/s+4.9J = 1/2*1kg*v^2 + 0J
4.9J = .5*v^2
2.45 m/s = v

I am not sure about how to get the height.

Thank you for any help

Attached Images
File Type: jpg table.jpg (69.0 KB)

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