Describe how predation is good for overall health of an ecosystem

Is this a scientific model? use complete sentences to explain why or why not. a graphic organizer showing the water cycle i need : ( asap i go it never mind

How can you use chemical equations to predict the products of the reaction you can carry out?

The alkali metals (group 1) consist of lithium (3), sodium (11), potassium (19), rubidium (37), cesium (55), and francium (87). they are soft, metallic solids with low densities and low melting points. based on the data shown in figure 1, how many valence electrons do alkali metals share?