Which of the following choices belongs at point 3 on this timeline?

Space is not completely empty. there are small particles in space. what happens when these particles come together?

The internal combustion engine was an innovation of

The venn diagram below shows some services provided by state and local governments. the answer choices are (1) - creating a police force, (2) - regulating taxicabs, (3) - regulating savings banks, (4) - issuing driver licenses.