Which of the following is an example of a closed system?
an estuary where fresh and ocean water mix
a chemical reaction within deep ocean organisms allowing them to glow
a living single-celled organism such as a phytoplankton
a river that flows into the ocean

Populations of blue-winged warblers, a type of bird, migrate south in the winter and return to canadian breeding grounds in the spring. as global temperatures have increased due to climate change, spring has started arriving in the warbler's breeding grounds earlier in the year, before the warblers return. warblers now arrive at their breeding grounds too late to select ideal nesting sites and to feed on important early-spring food sources how are populations of blue-winged warblers most likely to be affected by the earlier arrival of spring? o a. populations will go extinct since the warblers will stop migrating to breeding grounds. b. populations will be unaffected since most species can quickly adapt to effects of climate change. c. populations will increase since warmer temperatures are generally beneficial to survival, d. populations will decline since individuals will be less likely to successfully reproduce, reset next

7. describe two strategies that parents can use to cope with stress. 8. describe the three types of childcare available to families. 9. what can parents do to be more involved in their children's education at home and at school? 10. which factors should a parent consider when choosing a childcare option?

Group control group #1 experimental group yes yes yes control group #2 no new drug orange juice bed rest no yes no yes ves which of the following is the best explanation of why a second control group was included in this experiment? o a. to provide the volunteers in the study with something to drink o b. to prove that the common cold cannot be cured c. to confuse anyone who is trying to steal their new drug and sell it as their own invention o d. to researchers conclude that results are related to the new drug and not to the orange juice submit e previous