What type of reaction occurs without being started by some outside force a. spontaneous reaction b. physical reaction c. activation energy reaction d. backward reaction

Each pair of clay balls represents two planetesimals. if each planetesimal is composed of the same material and is separated he the same distance, which pair experiences the frayed gravitational attraction?

Aboy jumps into a cold swimming pool and his body tempature goes down hus muscles ,blood vessels

¿cómo demostraron los experimentos de griffith que un factor hereditario estaba involucrado en la transformación bacteriana?