<span>The poem was written for Thomas's dying father. It has no title other than its first line, "Do not go gentle into that good night", a line which appears as a refrain throughout. The poem's other refrain is "Rage, rage against the dying of the light".</span>
<span>Hope I helped. :) </span>
Using the formula:

Which is, 3.14 x 2^2 (radius is half of diameter)
Which equals 12.56.
Bonjour mon nom est Maddie!