In the quiz, the question asked: given theta1=10 degrees celsius, and theta2 = 10 degree celsius, and beta = 0.5, what is the v2 with and without bias correction.
I calculated v2 with bias correction like below:
v0 = 0
v1 = (0.5 * 0 + 0.5 * 10)/(1-power(0.5, 1)) = 10
v2 = (0.5 * 10 + 0.5 * 10)/(1-power(0.5, 2)) = 13.333

The answer does not have v2 = 13.333, is my calculation incorrect ?