what is the term for "the second of the four major islamic caliphates established after death of muhammed"

Brainliesttt !me : ) why were the eastern european countries attempting to break free of the soviet union?

When there are advances in technology, such as the personal computer, how might business productivity change? a) productivity is separate from technological advances so there is no impact. the new technology can replace outdated, less efficient, machinery. o) the businesses' products will no longer be demanded. d) manufactured items will be made elsewhere.

Select the correct answer. in what type of immunity will the defenses be triggered and react in the same manner, regardless of the organism invading? a. adaptive b. innate c. primary d. mechanical barrier