Which is the best definition of activation energy? the energy required to end a chemical reactionthe energy required to bind a substrate to an active site the energy required to break the bonds of reactant molecules the energy required to re-form bonds in product molecules

My question says on my assignment. read the following scenarios and decide which of the properties of life are being described. the first one is. katherine stopped on the way to school to grab some donuts. 2. because a dog cannot sweat, it has to pant in order to stay cool. 3. an elephant trun had no bone but 4,000 muscles. i have no idea what i am supposed to anwer. i can't find the answer in my notes or book that i can understand anyway

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?

Body temperature is tightly regulated in mammals for example when external temperatures drop too much the body of a mammal responds by in order to its core temperature?