NEED HELP ASAP i. Which runner, if either, is in the lead when t = 6.0 seconds? Justify your answer qualitatively without any equations.

ii. Justify your answer about which runner, if either, is in the lead when t=6.0 seconds using appropriate equations.

The graph is used to help answer the two questions above

The speed of light in a material is 0.50 c. what is the critical angle of a light ray at the interface between the material and a vacuum?

What is the mass of the same rock on the earth

The coulomb's law explains which of the following? select all the force between two charged objects is inversely proportional to the charge on each object. the force between two charged objects is directly proportional to the charge on each object. the force between two charged objects is directly proportional to the distance separating them. the force between two charged objects is inversely proportional to the square of the distance separat coulomb's law is similar to newton's 2nd law. if the force between two objects is f and the charge on both objects is doubled, the new force between the would now be 2f. if the force between two objects is 2f and the distance separating them is doubled, the new force between the objects would now o the be zf.