Your favorite taco stand is 800 m away, and closes in 15 minutes. How fast do you have to run to make it on time?

You must run at least 53.3333333 meters a minute.

adding a(n) to an electric circuit would increase the magnetic field around a wire;

b. solenoid

a solenoid is a type of electromagnet whose purpose is to generate a controlled magnetic field.

if the purpose of the solenoid is instead to impede changes in the electric current, a solenoid can be more specifically classified as an inductor rather than an electromagnet.

iron would move it is magnetic there is a mag field around the current in the wire