2. an example of a predator-prey relationship would be a. tree-water b. cow-grass c. hawk-mouse d. tick-dog 3. which of the following gasses is the result of life forms being present on earth? a. oxygen b. carbon dioxide c. water vapor 4.a. global warming b. absence of predators c. depletion of the ozone layer d. brush fires that destroyed the food supply 5.a. organs used in breathing b. food source c. method of reproduction d. pattern of movement 6. which of the following statements is true about organisms that are producers? a. they use energy from the sun to make food. b. they absorb energy from a host animal. c. they get energy from eating living plants. d. they get energy by breaking down dead plants and animals.

it can be observed without changing the identity of the object.

it depends on what substance you're talking about as well as many other factors. in quantum mechanics, the observation of particles affects the observers ability to measure certain properties. for example: you can know the velocity of a particle, but you can't know it's position; or you can know it's position, but not it's velocity. it's like trying to find out where a grain of sand is by throwing other grains of sand at it. once you find out where it is, it's been moved. it's also like trying to find an answer to the question of whether or not a tree falling in a forest makes a sound if nobody is there to hear it. paradoxically, the only way to find out is to be there and hear it.

hypostyle hall;