Dating the origin of the solar system relies on materials that formed at the very beginning and have stayed essentially unchanged since then. Meteorites provide the best source because they are primitive pieces from the early solar nebula that haven’t undergone extensive melting or differentiation. By applying radiometric dating to these meteorites, especially their calcium-aluminum-rich inclusions, scientists can measure ages around 4.56 billion years, which marks the time of the solar system’s formation. Moon rocks tell us about the Moon’s history, and distant galaxies aren’t directly tied to our solar system’s birth, while comets can be old but are harder to date precisely and don’t yield as robust a single age for the solar system as meteorites do.

The main idea is that in a smooth, steady fluid flow, faster speed means lower pressure. This comes from Bernoulli’s principle, which says the total energy per unit volume along a streamline stays nearly constant: pressure energy plus kinetic energy (related to velocity) add up with any height energy. When a region of the flow speeds up, its kinetic energy term ½ρv² increases, so the static pressure must drop to keep the total energy balanced. That’s why pressure decreases as speed increases. This explains everyday examples like air moving faster over the top surface of a wing, where the rapid flow lowers pressure and helps produce lift. So the correct idea is that pressure decreases with increasing speed.

Proteins are polymers built from amino acids, the basic units that define their structure and function. Each amino acid has an amino group, a carboxyl group, and a distinctive side chain; these units link together by peptide bonds through dehydration synthesis to form long chains. The sequence and chemical properties of the amino acids determine how the chain folds into a three-dimensional shape, which in turn enables the protein to carry out specific jobs such as speeding up reactions, signaling, or providing structural support. The other options correspond to building blocks of other biomolecules: nucleotides for nucleic acids, fatty acids for lipids, and saccharides for carbohydrates.

In stars, fusion builds heavier elements through successive burning stages: hydrogen fuses into helium, then helium burning creates carbon and oxygen. In the helium-burning phase, carbon is formed first via the triple-alpha process, and some carbon can capture another helium nucleus to become oxygen. So, among these elements, oxygen appears later in this stage than carbon. While stars can proceed to even heavier elements in later burning stages (neon, magnesium, silicon, iron), those options aren’t listed here, so oxygen is the last formed within the shown set.