Which of the following is the best definition of an atom? O A. A particle within the nucleus that has a neutral charge
B. A negatively charged particle that circles the nucleus
C. The fundamental unit of all matter, both living and nonliving
O D. A positively charged particle within the nucleus
SUBMI

Drag the correct tiles to the image. not all tiles will be used. the diagram is a schematic representation of the electron transport mechanism in mitochondria. label the diagram to complete the model.

Agroup of students is studying convection currents. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other in an area with warm air. after 10 minutes, the balloons are released from a height of 1 meter. which of the following do the students most likely observe? question 8 options: the cold balloon expands and rises. the warm balloon shrinks and sinks. the balloons rise at the same rate. both balloons are the same size. the ballons both rise. the cold ballon is larger than the warm balloon. the warm balloon expands and rises. the cold balloon shrinks and sinks.

How has biodiversity on earth changed over time?