Thermal Expansion-how much has the ocean expanded

[endurance12]

The ocean’s average temperature has risen by approx 0.375°C over the century. Use this value to estimate by how much the ocean water might have expanded in items of percentage increase.

This is what i started doing but I do not think this is right.
Coefficient of Cubical Thermal Expansion (Y)= change in volume (dv)/ Initial volume (v) * change in temp (dt)

Coefficient of volume expansion of water= 207*10^-6 per deg C
Linear coefficient = 1/3 cubical coefficient
=1/3*207*10^-6
= 6.9*10^-6%
But i am not getting the right answer I do not think. Can you please help me?

 

[CWatters]

Does the question ask for a percentage increase in depth (linear) or volume (cubic)?

 

[endurance12]

i believe volume

 

[haruspex]

Coefficient of volume expansion of water= 207*10^-6 per deg C
Linear coefficient = 1/3 cubical coefficient
=1/3*207*10^-6

If you think the question is asking for volumetric expansion, why divide by 3?

= 6.9*10^-6%

That's off by 3 orders of magnitude. Try the last step again.