How does a savanna differ from a grassland?
a.
savannas have a large number of grazing animals, while grasslands do not.
b.
savannas have shrubs and isolated trees, while grasslands contain grasses, flowers, and herbs.
c.
grasslands have burrowing animals, while savannas do not.
d.
savannas are regulated by fires, while grasslands are not.

Did the universe cool off or get hotter as it expanded after the 'big bang"?

Susie ran a race. she ran 55 miles an hour, and the race took her tt hours to complete.

In the image, layer a is the topmost layer. layer c contains fossils from the precambrian era. layer b contains dinosaur fossils, and layer a contains fossils of mammals. which two statements are supported by this evidence? 1. mammals lived before the precambrian era. 2. dinosaurs and mammals existed in the precambrian era. 3. dinosaurs evolved after precambrian organisms. 4. precambrian organisms evolved after dinosaurs. 5. precambrian organisms were the first life-forms to become fossilized, according to this sample.