A rock which has been transformed from shale is

Limestone's are very rich in

A. calcium

B. carbonate

C. calcium carbonate

D. magnesium carbonate

A crystalline or glassy rock formed when magma or lava cools down and solidifies is called

A. sedimentary rocks

B. metamorphic rocks

C. igneous rocks

D. morphic rocks

Obsidian is rich in

A. silica

B. iron

C. cobalt

D. calcium

Marble is transformed from

A. sandstone

B. limestone

C. igneous rock

D. shale

The continual process in which a rock is changed in to an another rock is called

A. rock cycle

B. rock sedimentation

C. sorting of rocks

D. accumulation of rocks