What was the difference between 

• the length of the Al 6063 sample while the force in question 2(c) is being applied, and
• the length of the Al 6063 sample after the force in question 2(c) has been released?

In other words, how much did the specimen retract once the force was removed?

Give your answer in mm, to at least 2 significant figures

What was the elastic modulus for the Al 6063 sample that you determined in question 2(b)?

Give your answer in GPa, to at least two significant figures