i need help asapppp

You are a marine paleontologist working on the sediments in
the Mediterranean Sea. Seventeen different locations have
been investigated. Over four months your team found and
collected material that may once have been a part of an
ancient seabed. If it was an ancient seabed, it is likely to
contain fragments of shells and other fossils. After careful
analysis, you found one chemical to be predominant in all
seventeen samples. The percentage composition of this
compound was found to be 40.00% calcium, 11.99% carbon,
and 48.01% oxygen. The molar mass of the unknown
compound is 100.09 g/mol.

1. Find the empirical and molecular formulae for the unknown
compound (substance X). What is the name of this
compound?