Yeast and sugar were added to lukewarm water and place in a flask. A balloon was stretched over the opening of the flask. Small bubbles were observed rising along the side of the flask as the balloon slowly began to inflate. It can conclude that ...

i think it is d. e because the next one is igneous.

level 4 to level 2 : ))

chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. these processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. some reactions produce heat and are called exothermic reactions and others may require heat to enable the reaction to occur, which are called endothermic reactions. understanding chemical changes is a major part of the science of chemistry.