That is because metamorphic rock is formed by parent rocks that are either sedimentary rock or igneous rocks and we can use the former rock type to distinguish the type of metamorphic rock, marble was igneous rock exposed to high pressure or temperature.
While the other two type of rocks are formed initially by sedimentation and volcanic movements and has no parent rocks.
The answer in finding the age of a sedimentary rock layer through radiometric dating can be assumed <span>between the absolute ages of the two igneous units.
Sedimentary rocks don't have radioactive elements so the beast way to know the age is through understanding what can elements in between can provide as evidence</span>
Volcanoes can release an amount of matter into the atmosphere. The particles will serve as nuclei to help form the water droplets. Following an eruption is usually a heavy rainfall that will encourage plant growth.
I am pretty sure it is Dallas