Answer:
Explanation:
Because they appeared quickly in geological time, and moulted like other arthropods, trilobites serve as excellent index fossils, enabling geologists to date the age of the rocks in which they are found. They were among the first fossils to attract widespread attention, and new species are being discovered every year.
Phase change is the change in state. i.e. water to steam or ice to water
Im going to say that its True.
Bone marrow transplant has been used successfully to treat diseases such as leukemias, lymphomas, aplastic anemia, immune deficiency disorders, and some solid tumor cancers
Elements [or radicals] with valency one are monovalent, those with valency two are divalent, and those with valency three are trivalent.
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What is the Valency of an Element / Radical?
Valency Divalent [2]
Element / Radical Oxide [Oxygen]
Symbol O
Ion O2-
