Which of the following statements is true? Dalton believed atoms were made mostly of empty space. Plasmas have a net negative charge. The number of protons in an element is always equal to the number of neutrons. Solids have a fixed mass, volume, and shape.

Will you chech and finish these for me, because i am stumped with them.

(science)study the following ocean currents map. an ocean currents map is shown. on the map the locations for san diego, california and savannah, georgia are marked. there is a looping current from the north past san diego and a looping current from the south near savannah which statement is most likely correct about the average temperatures in san diego, california as compared to savannah, georgia? it is higher in savannah because of the cool ocean currents from the south. it is higher in savannah because of the warm ocean currents from the north. it is lower in san diego because of the warm ocean currents from the south. it is lower in san diego because of the cool ocean currents from the north.

Will give brainliest! jay rides his 2.0-kg skateboard. he is moving at speed 5.8 m/s when he pushes off the board and continues to move forward in the air at 5.4 m/s. the board now goes forward at 13 m/s.a. determine jay’s mass.b. determine the change in the internal energy of the system during this process.(express your answer to two significant figures and include the appropriate units.)