The bunchberry flower has the fastest-moving parts ever observed in a plant. Initially, the stamens are held by the petals in a bent position, storing elastic energy like a coiled spring. When the petals release, the tips of the stamen act like medieval catapults, flipping through a 60? angle in just 0.30 ms to launch pollen from anther sacs at their ends. The human eye just sees a burst of pollen; only high-speed photography reveals the details.As FIGURE CP12.85 shows, we can model the stamen tip as a 1.0-mm-long, 10 μg rigid rod with a 10 μg anther sac at the end.Although oversimplifying, we??ll assume a constant angular acceleration.a. How large is the ??straightening torque???b. What is the speed of the anther sac as it releases its pollen?

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Pollen Pollen Anther sac 1.0 mm 60° `Stamen Initial configuration Final configuration FIGURE CP12.85