The smallest unit that makes up matter is an atom!
Endoskeleton- an internal skeleton, such as the bony or cartilaginous skeleton of vertebrates.
Exoskeleton- a rigid external covering for the body in some invertebrates animals, especially Arthropods, providing both support and protection.
Answer: metals.
Justification:
There are 118 elements which you can find in the periodic table ordered by atomic number. Those elements my be classified into metals, non-metals and metalloids.
The metals are placed on the left side of the periodic table. The metals share the properties of luster, conductivity and flexibility.
The properties of non-metals (which are on the right side of the periodic table) are opposite to those of metals: opaque, low conductivity and brittle.
Metalloids have in between properties.
Copper, for example is a metal: it has luster, is flexible and is highly conductive of the electricity (and temperature).
Time taken by the package to reach the sea level= 13.7 s
height=h=925 m
initial velocity along vertical= vi=0
acceleration due to gravity=g=9.8 m/s^2
using the kinematic equation h= Vi*t + 1/2 gt^2
925=0(t)+1/2 (9.8)t^2
4.9 t^2=925
t= 13.7 s