Replacement of CaO by PbO in soda-lime glass results in .

A. denser glass with a higher refractive index
B. a softer glass with a lower melting point
C. glass with a deep blue color
D. a harder glass with a higher melting point
E. opaque glass

The famous scientist galileo galilei did several experiments with sloping planes, which he rolled metal balls down so that he could study motion. by changing the slope, he could study how the speed at which the ball rolled was affected. what was the independent variable in galileo's experiment? a. the speed of the ball b. the slope of the plane c. whether the ball moved d. what the ball was made of