In the hierarchy of living things, animals from flat worms (platyhelminthes) to humans have two or more interacting to perform a task accomplished by one or more
a) tissues; organs
b) cell types; organs
c) cell types; tissues
d) organs; organ systems

According the inverse square law, doubling the distance from the source of the sound, a speaker, for example, will drop the sound 6 db each time. if you were standing in the back of an auditorium, 32 feet away from a speaker not using any amplification, would you be able to hear a speaker clearly? why or why not?

What do isotopes of uranium have the same number of? what do they have a different number of? a) same number of protons; different number of electrons b) same number of protons; different number of neutrons c) same number of electrons; different number of protons d) same number of neutrons; different number of protons

Which statement best describes a typical difference that could be found between the “analysis” and “conclusion” sections of a lab report?