After a massive-star supernova, what is left behind? a. always a white dwarf b. either a neutron star or a black hole c. always a neutron star d. either a white dwarf or a neutron star e. always a black hole

The summit of chimborazo, in ecuador, which is at a distance of about 6,384 km from the earth’s center. the bottom of the mariana trench, in the western pacific ocean, which is nearly 6,370 km from the center of the earth. on the surface of earth on the equator line.

At very high pressures, gases become and will eventually a) more dense; become hotter b) more dense; change to a liquid or solid c) less dense; combust d) less dense; turn into a liquid

Rohit is trying to tune an instrument