What is compression?
a.
stress squeezing an object
c.
stress breaking an object
b.
stress pulling an object
d.
stress releasing an object

Compression is stress squeezing an object. The correct option is A.

The word compression can be defined by the dictionary as an external force (stress) that tends to crush a material, squeezing its particles closer and shortening the dimension in the direction of its action.  

Squeeze refers to manage an object to get into or through a narrow or restricted space; firmly press (something soft or yielding), typically with one's fingers.

union blockade

explanation:

the union blockade in the american civil war was a naval strategy by the united states to prevent the confederacy from trading.

the blockade was proclaimed by president abraham lincoln in april 1861, and required the monitoring of 3,500 miles (5,600 km) of atlantic and gulf coastline, including 12 major ports, notably new orleans and mobile. those blockade runners fast enough to evade the union navy could only carry a small fraction of the supplies needed. they were operated largely by british citizens, making use of neutral ports such as havana, nassau and bermuda. the union commissioned around 500 ships, which destroyed or captured about 1,500 blockade runners over the course of the war.

the group i'm selecting: greeks.

a first group of greek immigrants came to the us in the 1850s. the second group came to america starting in the 1890s due to economic opportunities they didn't have back in their home caused by the hardships of ottoman rule. greek immigration was 90% male, many of them expected to work and return to greece after earning enough capital, but ultimately had to remain in the us after the greek genocide.