Single celled organisms exchange gases directly across their Cell membrane.
Answer:
the 2nd and 4th
Explanation:
they contain more than one molecule due to them being different elements
Answer:
Rocks across the ocean floor have alternating magnetic stripes.
Explanation:
Different types of evidence supported Hess's theory of sea-floor spreading: eruptions of molten material, magnetic stripes in the rock of the ocean floor, and the ages of the rocks themselves. This evidence made scientists take a second look at Wegener's hypothesis of continental drift.
