Theis a structure that supplies oxygen and nutrients to the fetus . a) amniotic fluid

b) endometrium

c) yolk sac

d) placenta

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Astudent poured a solution of bromothymol blue indicator into three test tubes. then he placed an aquatic plant in two of the test tubes, as shown below. he placed a stopper on each test tube and placed them all in the dark for 24 hours. bromothymol blue turns from blue to yellow in the presence of co2