Write the sub region of tropical region​

Which of the following is true about fossils? a. the relative age of fossils cannot be determined from their position in sedimentary layers. b. fossils found in lower layers of sedimentary rock are as old as fossils found in upper layers of sedimentary rock. c. fossils found in upper layers of sedimentary rock are older than fossils found in lower layers of sedimentary rock. d. fossils found in lower layers of sedimentary rock are older than fossils found in upper layers of sedimentary rock.

If a population is growing quickly in a small area then what must increase as well

The covers all of earth like a thin shell,but it is not a solid sheet of material.it is broken up into several large sections and many smaller ones. fill in the blank.