The horizontal axis of the cladogram depicted below is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. the labeled branch points on the tree (v-z) represent various common ancestors. let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species. 100,000 prese ale which of the five common ancestors, labeled v-z, is the common ancestor of the greatest number of species, both living and extinct?
a) v
b) w
c) y
d) z

Every compound can be represented by a chemical formula. a chemical formula is the set of symbols showing the elements that make up a compound and their proportions. water’s chemical formula is h 2 2 o. that means a molecule of water contains two atoms of hydrogen and one atom of oxygen chemically bonded. a molecule is a group of two or more atoms bonded together. molecules can range in size from two to thousands of atoms. a molecule of a compound is the smallest unit of that compound. every molecule of water has all the physical and chemical properties of water. that’s because every molecule of water is made of the same elements in the same proportions: two hydrogen atoms and one oxygen! which of the following is a true statement? a every molecule of the same compound will have different properties. b every molecule of a compound has the same proportion of elements. c molecules can be physically separated into smaller units of a compound. d molecules cannot be represented by chemical formulae.

Which of these serves as a reference for comparison during a scientific investigation? a)outcome variable (dependent variable) b) test variable (independent variable) c)control group d)hypothesis

What do lava flows made of aa indicate about the type of volcanic eruption that occurred? a. the eruption was viscous. b. the eruption was pyroclastic. c. the eruption was explosive. d. the eruption was quite. !