4. How do scientists know that dark matter exists? (1 point) O They assume that anything invisible has to be dark.
O Something has to be there to form superclusters.
The Redshifts give the dark matter away.
O They observe gravitational lensing bending the light of other objects in space.

Look at the potential energy diagram for a chemical reaction. which statement correctly describes the energy changes that occur in the forward reaction?

Suppose you have a box. which of these is not necessarily a true statement regarding the relationship between the force applied to the box, the work done on the box, and the distance the box is moved? a. if the box is not moved, no force is being applied to the box. b. if no force is applied to the box, no work is done on the box. c. if work is done on the box, then a force is applied to the box. d. if work is done on the box, then the box is moved a distance.

What structural formula represents 4 electrons shared between two atoms?