Briefly describe the three different ways of measuring the mass of a cluster of galaxies. do the results from the different methods agree? what do they tell us about dark matter in galaxy clusters?

.) the observation by semmelweis that more mothers died of childbed fever when their doctors also worked in the morgue

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.

higher potential

explanation:

because it is in a high speed so it must move into a of high potential