¿Cómo puedes hacer que un elemento que en principio no tiene posibilidad de atracción de metales se convierta en un imán?

Which of the following changes to a pipe would increase the conductance by a factor of 12? 1.quadrupling the length and tripling the radius.2.reducing the length by a factor of and doubling the radius.3.tripling the length and reducing the radius by a factor of .4.reducing the length but a factor of and doubling the radius.

Find the vertex(use the completing the square method), findthe x- and y-intercepts, and sketch the graph offunction. y = 2x2 + 4x - 1

James is trying to prove newton's 2nd law of motion. he tries to move four different objects with different masses, shapes, and sizes from point a to point b. the objects are a toy car, a car, a refrigerator, and a kitchen table. after some experimentation, he finds that force is dependent on the mass of the object, rather than it's size or shape. the object that takes the most force to move is the