Who discovered the exosphere, and when?

Let v1, v2, w be three linearly independent vectors in r 3 . that is, they do not all lie on the same plane. for each of the following (infinite) set of vectors, carefully sketch it in r 3 , and determine whether or not it is a vector space (i.e., a subspace of r 3 ). explain your reasoning

Aknife blade is a(n) a. lever b. screw c. wedge d. inclined plane

Aplane travels 1000 miles in 5 hours .what is the planes average speed?