HI! I NEED HELP ASAP!!
Why are electromagnets used in metal scrap yards?

A. They are temporary magnets, so they can be turned on and off.

B. They are very powerful permanent magnets.

C. They are weak permanent magnets.

D. They are temporary magnets, so eventually the metal just falls off.

Electroplating is a way to coat a complex metal object with a very thin (and hence inexpensive) layer of a precious metal, such as silver or gold. in essence the metal object is made the cathode of an electrolytic cell in which the precious metal cations are dissolved in aqueous solution. suppose a current of 480.ma is passed through an electroplating cell with an aqueous solution of agno3 in the cathode compartment for 46.0 seconds. calculate the mass of pure silver deposited on a metal object made into the cathode of the cell. round your answer to 3 significant digits. also, be sure your answer contains a unit symbol. ×10μ

The radius of a sphere is increasing at a rate of 9 cm/ sec. find the radius of the sphere when the volume and the radius of the sphere are increasing at the same numerical rate.

The device shows the relative humidity at 22°c. what’s the water vapor density if the maximum water vapor in air at this temperature is 20 grams/cubic meter? a device showing that at 22 degrees celsius the relative humidity is 58%. a. 11.6% b. 11.6 g/m3 c. 12.76% d. 12.76 g/m3 reset next