(Q).
Q: Elements below the second period, such as silicon, do not form what as readily as second-period elements, and when they do form, they are weaker than those formed by second-period elements? Choices: - covalent bonds - magnetic bonds - k. bonds - n bonds A:
(A).
n bonds

(Q).
Q: Connected to agriculture, forestry, mining, and urbanization, what is the single biggest cause of extinction today? Choices: - freshwater loss - hunting - global warming - habitat loss A:
(A).
habitat loss

(Q).
Q: Mosses, liverworts, and hornworts are examples of what type of plant in which gametophyte generation is dominant? Choices: - choanocyte plants - vascular plants - photoreactive plants - nonvascular plants A:
(A).
nonvascular plants