Questions

The first of the four stages of coal formation is lignite coal.

There are four stages of coal formation:

1. Peat,

2. Lignite,

3. Bituminous and

4. Anthracite.

The bacteria has removed a large portion of the other constituents of the plant matter and left around 25 to 34 percent.

High-end: Intel - Pentium (II, III, 4) AMD - Athlon. Low-end: Intel - Celeron, AMD - Duron. 64-bit: Intel - Itanium 2, AMD - Opteron.

Wherever on earth we hold a compass, the needle points towards the magnetic North Pole. A compass is a great tool for navigation.

Compass is widely used in aircrafts, ships, military services,...

Covalent type of bonding joins The two hydrogen atoms are joned by Covalent type of bonding.

In this type of bonding, electrons are shared between the atoms in order to fill there valence shells. Thus sharing of electrons take place in between the hydrogen atoms.

From the given data,

11+ 11 = 4 => 1 + 1  +  1 + 1 = 4

12 + 12 = 6 => 1 + 2  + 1 + 2 = 6

13 + 1 3 = 8 => 1 + 3  + 1 + 3 = 8

Similarly,

14 + 14 = 10 => 1 + 4  +  1 + 4  = 5 + 5 = 10

Stratification as actually the settling down of sediments with different properties to form layers/strata over years. Stratification especially occurs on the bed of water bodies such as oceans.

Stratified sedimentary rocks are used to study the ecological conditions over previous years/eras.  

The other choices like Windstorms, Glacial Ice and Stream water are mediums which sediments are transported.