What did the miller-urey experiment demonstrate?

a. earths early atmosphere contained abundant oxygen
b. early earth was constantly bombarded with comets.
c. small organic molecules formed from gas mixture of earth's early atmosphere.
d. organisms were spontaneously generated on early earth.

Some technological solutions to problems like global warming meet the specific needs and situations of local communities. an example from india involves converting the solid waste from cattle into clean-burning fuel for cooking. this reduces the amount of greenhouse gases, specifically methane and carbon dioxide, released into the environment from wood fires. when evaluating the feasibility of implementing this solution, computer models are used to weigh costs against benefits. what factor is least likely to impact the decision on adopting this technology?

The pharynx is the structure in the body that serves as a pathway of both air and food. how does the body make sure that food does not get into the lungs? the salivary glands secrete enzymes that pull food out of the air pathway. the small intestine pushes the air out of the digestive system. the pancreas breaks down food in the air pathway. the epiglottis closes the air pathway so that food will not enter it.

Below, the levels of organization in a multicellular organism are shown from least to most complex. which level of organization can be described as several different types of tissues working together to perform a common task?