Which of these best describes the role of plants in the carbon-oxygen cycle? a. to absorb oxygen from the atmosphere and release carbon dioxide into the atmosphere b. to absorb carbon dioxide from the atmosphere and use it to make sugar c. to absorb oxygen from the soil and use it to make carbon dioxide for sugar production d. to absorb carbon dioxide from the atmosphere and release it back into the atmosphere

Grignard reactions are highly exothermic and are performed in ether solvent. there is a real risk of fire during this reaction. in the case that a fire should occur in your distillation apparatus, what is the best course of action? g

Recent research by marine biologists suggests that bottlenose dolphins have names for themselves. scientists played sounds they had identified as the names of particular dolphins, putting them through a synthesizer so that they did not sound like the voices of particular dolphins. the researchers found that dolphins would respond to the names of other dolphins that they were related to or associated with, but they ignored the names of strangers. this discovery suggests a much greater degree of self-awareness in aquatic mammals than was previously suspected. if this research holds up, what does it suggest about dolphins?

18. which statement about cancer is true?