Find the angle between the following vectors, as a function of a:
u = < 2, a>
v = < -1,5>

i know how to find the angle between two vectors, but i dont understand how to find this angle.

Plz heeeeeeelp plz give me the answer

Rockwell hardness of pins of a certain type is known to have a mean value of 50 and a standard deviation of 1.1. (round your answers to four decimal places.) (a) if the distribution is normal, what is the probability that the sample mean hardness for a random sample of 8 pins is at least 51?

Manuela claims that and are congruent. which statement best describes her claim? she is incorrect because the segments do not have the same orientation. she is incorrect because the segments do not have the same length. she is correct because the segments have the same length. she is correct because the segments have the same orientation.