How is frequency related to the sound we hear?

The dot diagram represents the motion of the motorcycle as it moves from left to right

Which body part transports oxygen removes waste materials in carries nutrients to the body as part of the circulatory system

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