Loretta and her friends want to find out which of their pets can run the fastest. Which kind of scientific investigation should they use? A. a field study
B. a controlled experiment
C. development of a model
D. a review of existing work

What material does not melt at any temperature

How many moles is 14.5 cm^3 of platinum? the density of platinum is 21.45 g/cm^3.

Which theory was contradicted by experiments with the photoelectric effect? light spreads out after it passes through a small opening. as soon as light strikes metal, electrons will be ejected. visible light, regardless of color, will cause the ejection of electrons when striking metal. the kinetic energy of ejected electrons depends on the frequency of light that strikes the metal.