The circulatory system is divided into two main parts, the ___ circulation and the pulmonary circulation. a. atrium b. muscular
d. systemic

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.

answer by yourhope:

answer is

human impact on the environment can be seen in the deterioration of the !

: )

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