Answer:
This:
Explanation:
Black holes occur when a massive star or larger reaches the final stage of it's lifespan. The star implodes and a black hole is the dying star's remains
Copper has a FCC i.e. face centered cubic crystal structure. The 100 plane is essentially a planar section of the cubic cell where 4 Cu atoms occupy the 4 corners of the plane along with 1 Cu atom at the center of that plane. Each of the Cu atoms in the corners is shared by 4 adjacent unit cells. Thus, there are 2 Cu atoms present in the 100 plane (4*1/4 + 1 = 2).
Now, the planar density PD along the 100 plane is given as:
PD(100) = # atoms in the 100 plane/Area of 100 plane
=
Here R = radius = 0.128 nm = 
PD = 
Tropical Zones
*Tropic of Cancer
*Tropic of Capricorn
I cant see it though
Carbon has the ability to form multiple bonds because it has four valence electrons. Having four valence electrons means that carbon has a lot of space to form bonds with other atoms, or multiple bonds, in order to reach the full octet.
Hope this helps!! :)