Scientific models . a.
are based on a set of observations
b.
are used to replace experiments
c.
allow the study of existing systems only
d.
are rarely used

Which term describes the number of waves that pass a given point in a given time? crest frequency trough wavelength

Which of the following types of stars is most likely to end up as a supernova? in graph a, the curve peaks at 800 nm, in the red section of the visible light spectrum. in graph b, the curve peaks at 550 nm, in the green section of the visible light spectrum. in graph c, the curve peaks at 450 nm, in the blue section of the visible light spectrum. in graph d, the curve peaks at 300 nm, in the violet section of the visible light spectrum. a b c d

Which kind of worm has a closed circulatory system? a planarian b fluke c pinworm d an earthworm