Air mass, letter a is the correct one
Answer:
Coronaviruses are named for the crown-like spikes on their surface. There are four main sub-groupings of coronaviruses, known as alpha, beta, gamma, and delta.
Human coronaviruses were first identified in the mid-1960s. The seven coronaviruses that can infect people are:
Common human coronaviruses
229E (alpha coronavirus)
NL63 (alpha coronavirus)
OC43 (beta coronavirus)
HKU1 (beta coronavirus)
Other human
It was Alps its located in the south central Europe, they extend for almost 700miles from the coastline of southern france
What mountain range is found in the south central europe ::: ALPS IS THE MOUNTAIN.
Liquid water cannot persist at the moon's surface, and water vapor is decomposed by sunlight, with hydrogen quickly lost to outer space. However, scientists have since the 1960s conjectured that water ice could survive in cold, permanently shadowed craters at the Moon's poles.
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