Estion 3 A column or combination of columns in one table that refers to a primary key in the same or another table

Robots with telescoping arms are sometimes used to perform tasks (e.g., welding or placing screws) where access may be difficult for other robotic types. during a test run, a robot arm is programmed to extend according to the relationship r = 3 + 0.5cos(4θ) and the arm rotates according to the relationship θ=−π4t2+πt , where r is in feet, θ is in radians, and t is in seconds. use a computer program to plot the path of tip a in x and y coordinates for 0 ≤ t ≤ 4s.

Description: write function lastfirst() that takes one argument—a list of strings of the format "lastname, firstname" —and returns a list consisting of two lists: (a) a list of all the last names (b) a list of all the first names

22. sata3 allows for data transfer rates of 600 mb/s. explain why you would likely not be able to copy data from one hard drive to another at anywhere close to this speed. also, what could be upgraded on the computer to achieve transfer speeds closer to 600 mb/s