Here's why:
* Granite is an igneous rock, formed from cooled magma.
* Shale is a sedimentary rock, formed from compressed mud and clay.
* Coal is a sedimentary rock, formed from compressed plant matter.
* Limestone is a sedimentary rock, formed from the accumulation of marine organisms' shells and skeletons.
These are all distinct types of rocks with different origins and compositions. They are not typically classified together as a single group.
Possible ways to group these rocks:
* Sedimentary Rocks: Shale, coal, and limestone are all classified as sedimentary rocks.
* Rocks with different origins: Granite (igneous), shale, coal, and limestone (sedimentary).
* Rocks used in construction: Granite, limestone, and sometimes shale can be used as building materials.
Let me know if you had a different grouping in mind, and I'll do my best to answer!
