PLEASEE HELP ME! PLS PLS I NEED IT NOW PLS!

iron Bars form a solenoid when wrapped in a coil by a current carrying copper conducting wire .

copper coils generate a magnetic field when a current is passed through the coil . according to the helmholtz law.

under a microscope, cancer cells may look very different from normal cells. they often have different sizes and some may be larger than normal while others are smaller. cancer cells are often abnormally shaped and the control centre of the cell (the nucleus) may have an abnormal appearance.

i think? ?

it is the most commonly accepted one