The core of a star must be at temperature of degrees celsius for hydrogen fusion to take place. 10,000 100,000 1,000,000 10,000,000 100,000,000

An equinox occurs when a. neither end of earth's axis is tilted toward or away from the sun. b. the north end of earth's axis is tilted away from the sun. c. the north end of earth's axis is tilted toward the sun. d. earth's axis is parallel to the sun's rays. select the best answer from the choices provided a b c d

Which is the best predictor of the radioactive nature of an isotope? o the proton-to-electron ratio the neutron-to-proton ratio o the neutron-to-electron ratio the electron-to-proton ratio

Which lists the organs in the correct order as food passes from the mouth to anus?