The period of the embryo begins at and ends with which takes about ) conception; birth; nine monthsb) the first trimester; implantation into the uterine wall; twelve weeksc) week 3; formation of bone cells; six weeksd) organogenesis; ossification; one trimester

a) conception; birth; nine months

Explanation:

The period of the embryo begins at conception and ends with birth, which takes about nine months.

An embryo is formed when the male and female gamates meet in the process of fertilization, this is called conception. The pregnancy last for about nine months and ends with the birth of a child.

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according to classical republican political theory, which democratic republics would function best?

a.   small republics, with people who had similar interests

b.   large republics, with people who had competing interests

c.   republics made up entirely of landowners

d.   republics made up entirely of servants