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1500 - 3200 yards (1372 - 2926 m)
The yardage of the sweater is this. Each skein of the Habu has 763 yards. You would need however many yards at the proper gauge for your size.
To use circular needles for an open front, you just knit back and forth as if they were straight needles. This allows you to hold all the stitches on one needle.
Many of us only use circular needles for all patterns.