Which of the following is true about a family psychologist?

What are the north and south poles of a solenoid change with?

Aprotein molecule in an electrophoresis gel has a negative charge. the exact charge depends on the ph of the solution, but 30 excess electrons is typical. what is the magnitude of the electric force on a protein with this charge in a 1600n/c electric field? write in two significant numbers, and also in newton

Which atomic model is missing from this set