The nucleus or center _area of the atom contains two kinds of subatomic particles. which two?
a) protons and electrons
b) protons and neutrons
c) electrons and neutrons
i think it's a

Dying the folding patterns of protein molecules can microbiologists better understand cellular processes as well as some diseases, such as alzheimer’s, that are caused by proteins that have misfolded. the folding of these complicated molecules can be simulated on computers, but it takes a lot of processor power and time for even expensive supercomputers to do this. a group of researchers at stanford university developed software that can be used to distribute the processing of data to anyone who is willing to donate time on their idle personal computers. as a result, the researchers have been able to achieve protein-folding simulations that are far better than those other computing methods have done. which statement best describes the work of these researchers? the work is not scientific because the data are not processed in one location. the work is not scientific because the simulations are not reproducible. the researchers applied creativity to solve a problem in running an experiment. the researchers used only well-established scientific techniques.

Astudent carefully transfers 30 g of water and 30 g of alcohol in a glass tube, forming two layers and filling the tube completely. after sealing the tube, the student mixes the solutions, and notices a bubble that forms in the tube. what is the mass of the contents in the glass tube after mixing?

What mass of natural gas (ch4) must you burn to emit 276 kj of heat?