For each problem, define whether you are calculating for a scalar or vector quantity. Show your work to receive full credit. A skateboarder travels 200 m in 3,380 secs. What is the speed of the skateboarder?

Schrodinger and heisenberg developed an alternate theory about atomic nature that contradicted some of bohr's model of the atom. how do changes resulting from new technology and evidence affect the reputation of the atomic theory?

Classify this reaction: 2al+n2-> aln.

Which property of a rock remains unchanged by mechanical weathering? a. total surface area b. size and shape c. mineral composition d. sharpness