Morpheme is the smallest unit of language that carries meaning. It can be a root word or a bound or free affix that changes meaning or grammatical function. For example, in cats, there are two morphemes: cat (the core meaning) and -s (the plural marker). In unhappiness, there are three morphemes: un- (not), happy (the core meaning), and -ness (a state or condition). Some morphemes must be attached to others (bound morphemes), like prefixes and suffixes, while others can stand alone as words (free morphemes) like book or run. Phoneme, by contrast, is the smallest sound unit that can distinguish words, but it doesn’t carry meaning by itself. Allophones are variant pronunciations of a phoneme that don’t change meaning, and graphemes are written symbols representing sounds or letters, which may or may not align with morphemes.

Decibels turn a ratio into a logarithmic value, and for power or intensity quantities the conversion uses a factor of 10. dBIL measures intensity level by comparing the measured intensity to a reference intensity, so it uses the ratio of the two power-like quantities. Since Wo represents the measured power (or intensity) and Wr the reference, the correct expression is 10 log(Wo/Wr). Using 20 log would apply to amplitudes like voltage or field strength, not power; flipping the ratio would invert the sign, and mixing in a different reference (Pr) would not match the standard definition of dBIL.

The idea being tested is that Senior High School is completed in two years, with students advancing through core subjects shared by all tracks plus track-specific courses each year, and finishing with a capstone that brings together what they’ve learned. This two-year sequence allows depth in both general and specialized learning, culminating in a capstone project or presentation that demonstrates integration across subjects. The other descriptions don’t fit the actual structure: three years without a capstone don’t reflect the required end-project, one year isn’t enough time for core plus track subjects, and four years with multiple capstones adds extra time and requirements that aren’t part of the standard SHS progression.

Compression describes the region where air molecules are pushed close together. Sound travels as a longitudinal wave, with particles oscillating along the direction of travel. In a compression, density and pressure rise because the molecules are squeezed into a smaller space. The wave then alternates with rarefaction, where molecules spread out and pressure lowers. Frequency and amplitude describe how often the wave repeats and how strong the pressure variation is, not the spacing of molecules. So the term for air molecules that are close together is compression.