Which best explains why a firework being ignited is an example of an exothermic reaction and not an endothermic reaction? A)The fireworks produce colors.

B)The fireworks give off heat.

C)Igniting the fireworks requires energy

D)Igniting the fireworks makes an odor.

What three things determine the shape and size of a puddle when water is poured out onto a surface

The chart shows the bid provided by four contractors to complete a job. which contractor is the most cost-effective?

Which are examples of how technology has advanced scientific understanding.1using hot water to sterilize medical equipment.2transplanting a human organ into another individual.3inserting genes from one sheep into another cell to make a cloneunderstanding the different structures that make up a cell.4examining microorganisms from the deepest parts of the ocean