This is an incomplete question, the given sketch is shown below.
Answer : The name of given unit cell is, FCC (face-centered cubic unit cell)
Explanation :
Unit cell : It is defined as the smallest 3-dimensional portion of a complete space lattice which when repeated over the and again in different directions produces the complete space lattice.
There are three types of unit cell.
- SCC (simple-centered cubic unit cell)
- BCC (body-centered cubic unit cell)
- FCC (face-centered cubic unit cell)
In SCC, the atoms are arranged at the corners.

The number of atoms of unit cell = Z = 1
In BCC, the atoms are arranged at the corners and the body center.

The number of atoms of unit cell = Z = 2
The given unit cell is, FCC because the atoms are arranged at the corners and the center of the 6 faces.

The number of atoms of unit cell = Z = 4
Thus, the name of given unit cell is, FCC (face-centered cubic unit cell)
Answer:
12.5%
Explanation:
Initial percentage of carbon 14 = 100%
Final percentage = ?
Time passed = 17.1 * 1000 years = 17100 years
Half life of carbon 14 = 5,730 years.
So how many Half lives are in 17100 years?
Number of Half lives = Time passed / Half life = 3.18 ≈ 3
First Half life;
100% --> 50%
Second Half life;
50% --> 25%
Third Half life ;
25% --> 12.5%