In the reaction, al2o3 + 6 hcl → blank space + 2alcl3, what coefficient should be placed in front of h2o to balance the reaction?
question 9 options:
a. 1
b. 2
c. 3
d. 6

The large ground finch obtains food by cracking seeds. what is its short, strong beak an example? a) tendency toward perfection b) adaptation of a species over time c) selective use and disuse of an organ over time d) scarcity of recourses

Which medullary index indicates a human hair? a. 0.653 b. 0.733 c. 0.516 d. 0.256

Which would be the most useful source of evidence to support mcneill's contention?