Ariver has different populations of lampreys and paddlefish. the paddlefish feed on zooplankton, while the lampreys feed on the paddlefish. humans living around the river hunt the paddlefish. what will happen to the ecosystem if the paddlefish are hunted in excess?

The answer is: The population of paddlefish will decrease, while the population of zooplankton will increase.

The paddlerfish is predator to zooplankton. An decrease in predator (in this example the paddlerfish) will increase the number and genetic variation in a population of zooplankton.

An decrease of food (in this example the paddlerfish) will decrease population of the lampreys.

Hman activity (hunting) decrease population of the paddlerfish.

answer is: c. the experiment shows that the red substance experienced a chemical change.

this is chemical change (chemical reaction), because two new substances are formed (metalig liquid and gas), the atoms are rearranged and the reaction is followed by an energy change.

this is example of chemical decomposition.

chemical decomposition (analysis) is the separation of a single chemical compound into its two or more elemental parts or to simpler compounds.  

chemical decomposition is opposite of chemical synthesis.