With no explanation, label text_A→text_B with either "DON'T KNOW", "NO" or "YES".
text_A: Around this time Johann Bernoulli's two sons, Daniel and Nicolaus, were working at the Imperial Russian Academy of Sciences in Saint Petersburg. On 31 July 1726, Nicolaus died of appendicitis after spending less than a year in Russia. When Daniel assumed his brother's position in the mathematics/physics division, he recommended that the post in physiology that he had vacated be filled by his friend Euler. In November of 1726, while Euler was trying, ultimately without success, to become a professor of physics at the University of Basel, he accepted this offer with glee, but did delay traveling to Saint Petersburg while waiting to hear from Basel
text_B: Given the outcome of the hiring process, would Euler be lecturing to his students in Russian?
YES.