(Q).
Q: The ordovician-silurian extinction event is the first recorded mass extinction and the second largest. during this period, about what percent of marine species went extinct? Choices: - 10 percent - 99 percent - 40 percent - 85 percent A:
(A).
85 percent

(Q).
Q: What compounds contain only carbon and hydrogen? Choices: - carbonates - particles - molecules - hydrocarbons A:
(A).
hydrocarbons

(Q).
Q: What does sexual reproduction with gametes and fertilization produce? Choices: - haploid zygote - sister chromatids - identical twins - diploid sporophyte A:
(A).
diploid sporophyte