Which line is written in iambic pentameter? i, my dear, was born to-day – for every atom belonging to me, as good belongs to you the earth can have but earth, which is his due even as herself, o friend!

The line written in iambic pentameter is "The earth can have but earth, which is his due".

The Iambic pentameter is an expression of metric that is used to categorize a certain rhythm in a line. We recognize rhythm dividing the line into groups of syllables, which are called feet. The iambic rhtythm presents the use of an unstressed syllable followd by a stressed syllable. We call it a "pentameter" when it's made up of five "feet". Usually, lines of this kind are composed of ten syllables as a result like we see on the line you were given.

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