​A battery generates what type of current? Yesterday's question was "Appearing approximately 2.7 billion years ago, the first oxygen producing organisms most likely belonged to what group of bacteria?" The answer was cyanobacteria, or blue-green algae or bacteria.

​Appearing approximately 2.7 billion years ago, the first oxygen producing organisms most likely belonged to what group of bacteria? Yesterday's question was "To a chemist, the term “organic” means that a compound is based on what element? " The answer was carbon.

​To a chemist, the term “organic” means that a compound is based on what element? Yesterday's question was "Within our solar system, what are the four Jovian planets?" The answer was Jupiter, Saturn, Uranus, and Neptune.

​Within our solar system, what are the four Jovian planets? Friday's question was "Hydraulic fracturing is a natural gas mining technique that targets what kind of sedimentary rock?" The answer was shale.

​How many DNA nucleotide [NOO-klee-uh-tyd] bases are required to code for a single amino acid? Yesterday's question was "A battery generates what type of current?" The answer was DC or Direct Current.