On<span> November 10, 1958, Soviet Premier Nikita Khrushchev delivered a speech This ultimatum sparked a three year </span>crisis<span> over the future of the city of </span>Berlin <span>that culminated in </span>1961<span> with the building of the </span>Berlin Wall<span>.</span>
In this context alliance would mean to come to a formal agreement to help each other.
Answer:
https://www.nasiol.com/about-nanotechnology/?gclid=Cj0KCQjwxIOXBhCrARIsAL1QFCZHw6fcd_dTT4AjtdAto8Ij9j-vaRmSefL2icWh6L3oCSqaqt2bAY8aAjNiEALw_wcB
