The main concept of relational databases was published in 1970 by:

the berlin blockade was an international crisis that arose from an attempt by the soviet union, in 1948–49, to force the western allied powers (the united states, the united kingdom, and france) to abandon their post-world war ii jurisdictions in west berlin. in march 1948 the allied powers decided to unite their different occupation zones of germany into a single economic unit. in protest, the soviet representative withdrew from the allied control council. coincident with the introduction of a new deutsche mark in west berlin (as throughout west germany), which the soviets regarded as a violation of agreements with the allies, the soviet occupation forces in eastern germany began a blockade of all rail, road, and water communications between berlin and the west. on june 24 the soviets announced that the four-power administration of berlin had ceased and that the allies no longer had any rights there.

the correct answer is b, "fertility rates are increasing, so populations will grow more quickly in the future."

i do believe its (d) it allowed the government to offer pioneers sixty acres of western land if they lived on it and made improvements to it.

explanation: signed into law in may 1862, the homestead act opened up settlement in the western united states, allowing any american, including freed slaves, to put in a claim for up to 160 free acres of federal land. by the end of the civil war, 15,000 homestead claims had been established, and more followed in the postwar years

the puritans were a group of people who grew discontent in the church of england the common unity strengthened the community.