With what speed are pollen grains ejected from a bunchberry flower?

The flowers of the bunchberry plant open with astonishing force and speed, causing the pollen grains to be ejected out of the flower in a mere. 3 ms at an acceleration of 2.5 * 104 m/s^2. The grains are ejected from the flower at 7.5 m/s.

So, in summary, your final answer is 7.5 m/s