Which organism in an ecosystem is likely to be found at the top of an energy pyramid ?

insect

hawk

frog

grass

(1) fire extended humans’ geographical boundaries by allowing them to travel into regions that were previously too cold to explore. (2) it also kept predators away, allowing early humans to sleep securely. (3) fire, in fact, has been a significant factor in human development and progress in many ways. (4) other obvious benefits of fire are its uses in cooking and in hunting. (5) probably even more important, however, is that learning to control fire allowed people to change the very rhythm of their lives. (6) before fire, the human daily cycle coincided with the rising and setting of the sun. (7) with fire, though, humans gained time to think and talk about the day’s events and to prepare strategies for coping with tomorrow. the sentence that expresses the main idea is: (type the number of the sentence. then click “go.”)

Which word best describes the author's tone in this excerpt from "that spot" by jack london? i don’t think much of stephen mackaye any more, though i used to swear by him. i know that in those days i loved him more than my own brother. if ever i meet stephen mackaye again, i shall not be responsible for my actions. it passes beyond me that a man with whom i shared food and blanket, and with whom i mushed over the chilcoot trail, should turn out the way he did. i always sized steve up as a square man, a kindly comrade, without an iota of anything vindictive or malicious in his nature. i shall never trust my judgment in men again. why, i nursed that man through typhoid fever; we starved together on the headwaters of the stewart; and he saved my life on the little salmon. and now, after the years we were together, all i can say of stephen mackaye is that he is the meanest man i ever knew. a. excited b. ironic c. indignant d. playful

Read the paragraph. in fact, teenagers contribute a great deal to their community. this is another reason why they must be taken into account when public policy is debated. over eighty percent of teens spend time volunteering at their schools and other organizations. this is an example of statistical analysis layering point of view outlining