Physical and chemical changes and properties are observed and tested in order to confirm the identity of a substance or how a substance may act in certain condition. The image below is a rock that, based on its bright yellow color, scientists believe to be sulfur. However, they would like to use a test to confirm this prediction. Which procedure would you recommend the scientists use?

(A) Use volume displacement and the mass of the rock to calculate density.

(B) Measure volume in centimeters cubed and add to mass to determine density.

(C) Find the weight and volume of the rock then multiply to calculate density.

(D) Dissolve the rock in water, then find the mass and volume needed to calculate density.

Which explanation is true about what happens to a ray of light when it strikes a mirror? a. a light ray is transmitted toward a mirror at a certain angle. the light ray is then reflected by the mirror at an equal angle but in the opposite direction of the transmitted ray. b. an incident ray strikes a mirror at an angle with a line perpendicular to the mirror. the light ray is then reflected at an angle equal to the angle of incidence but on the opposite side of the perpendicular line. c. a reflecting ray strikes a mirror at an angle with a line perpendicular to the mirror. the light ray is then refracted at an angle equal to the angle of the reflecting ray and on the same side of the perpendicular line. d. an incident ray strikes a mirror at an angle with a line parallel to the mirror. the light ray is then transmitted at an angle equal to the angle of incidence but on the opposite side of the parallel line. you so much! : -d take the time to try and answer correctly.