Question

1. types of rocks song: finish the chorus line: it starts with any rock type and then travels the cycle these are types of rocks these are types of rocks

Explanation:

The rock cycle involves three main types of rocks: igneous, sedimentary, and metamorphic. The song about the types of rocks (relating to the rock cycle) would have the chorus line finish with "these are types of three rocks" (referring to the three main rock types) or more specifically, the standard song about the rock cycle's chorus for this line is "These are types of three rocks" (igneous, sedimentary, metamorphic) or sometimes the lyric uses "these are types of rock" but in the context of the cycle and three types, the correct fill - in related to the three main rock types. However, the most common lyric for this "TYPES OF ROCKS SONG" chorus line when talking about the rock cycle and the three rock types is that the blank is filled with "three" (as there are three main rock types: igneous, sedimentary, metamorphic) or sometimes the lyric is structured to refer to the three types. Alternatively, if the song is about the three rock types, the blank should be "three" (or the three rock types' collective reference, but the typical fill here is "three" to denote the three main rock types in the cycle).

Answer:

three