What do i need to put in the empty blanks?

Which of the following was not a major animal on land during the carboniferous period? amphibians insects both a and b none of the above

1. in what ways have non-native species been beneficial? 2. what are some of the hypotheses for the collapse of honeybee colonies? 3. distinguish between regional and functional extinction. 4. why is it difficult to measure background extinction rates? 5. what three factors are most important in causing extinction rates to climb?

Technology can bring both good and bad things. pesticides can make crops more resistant to insects (good) but can harm humans if they are used improperly (bad). give examples of both the good and bad