3. which of these is true about inherited traits?
a. traits always follow simple patterns of inheritance.
b. traits may be determined by multiple genes.
c. all traits are inherited from only one parent.
d. every trait is controlled by only one gene.

a- all cells come from pre-existing cells

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.