National parks reduce the human impact on land by a. permitting limited human development. b. cleaning up litter c. preventing human development d. preventing companies from polluting on public lands select the best answer from the choices provided

Name the part of the the brain labeled "e".

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

24. how are vaccines used to keep people healthy?