What is an example of a closed system?
a.) an estuary where fresh and ocean water mix
b.) a living single-celled organism such as a phytoplankton
c.) a river that flows into the ocean
d.) a net constructed along a section of the river to separate the foreign fish species from the rest of the river

What will happen to a population of predators if there is a sudden, temporary increase in the number of prey? a. the population of predators will be uniform with no change. b. the population of predators will increase first and then decrease slowly. c. the population of predators will increase continuously.

Dr. kaylan is an ecologist who studies bird behavior. she sets up an experiment to test which type of food crows are most likely to eat when given a choice between walnuts, corn, and sunflower seeds. to perform her experiment, dr. kaylan places three food bins in an area frequented by cows. each bin contains one of the three food types. then, she measures how much of each food type is eaten every day for a month and summarizes the results of her experiment in the pie chart below. based on her results, dr. kaylan concludes that crows choose to eat corn more frequently than other food sources because it has a higher nutritional value. what is a reasonable alternate conclusion that can be drawn from dr. kaylan's data

A60-tooth gear is connected to a 72-tooth gear.if the smaller gear turns 12 times,how many turns does the larger gear make?