During which era did the first dinosaurs appear? triassic jurassic cretaceous devonian

[ou.01jthe greatest speed with which any physical object moves is 300,000 km/soundsec. which of the following has a speed of 300,000 km/sec? a. light in water b. light in vacuum c. sound in air. d. sound in water

What two advantages do the coastal countries of west africa have over the sahel countriesfertile soil and mineral resources temperatures and terrain human resources and natural resources weather patterns and location

When geographers describe how two places are related to each other spatially, they are describing a. where the places are located in relation to one another b. what kinds of natural environments are around each place c. how each place is changing over time d. what kinds of cultures are in each place