What guards are ok to remove on mechiney

During which phase does earth see more than half of the moon's surface? 1)first quarter2)third quarter3)waxing gibbous4)waning crescent

Explain the source of radioactivity in uranium in earth’s crust by which it produces nuclear radiation

What are two ways that harvesting algae from the ocean may benefit human society? how might the harvest of algae negatively impact the ocean communities where that algae grows? how could this be prevented?