Fossil Fuels:
Coal and Oil
How they are formed:
Coal is formed from big plants, from a long time ago. When the big plants died, they formed layers at the bottom of swamps and the dirt began to pile up and it formed Coal.
Oil is a fossil fuel that has been formed from a large amount tiny plants and animals such as algae and zooplankton.
Answer:
B and D could both be right as they are quit similar.
Consider two rods of the same length and diameter,
Increasing the diameter of one would change the expansion qualities of that rod even though there would be no chemical changes,
However, leaving the physical appearance of both rods the same while applying a reactive substance (acid or something) to one of the rods would not necessarily change the physical appearance of that rod but could make a considerable change in the physical properties of that rod.
Answer:
a) 2.41 km
b) 38.8°
Questions c and d are illegible.
Explanation:
We can express the displacements as vectors with origin on the point he started (0, 0).
When he traveled south he moved to (-3, 0).
When he moved east he moved to (-3, x)
The magnitude of the total displacement is found with Pythagoras theorem:
d^2 = dx^2 + dy^2
Rearranging:
dy^2 = d^2 - dx^2
The angle of the displacement vector is:
cos(a) = dx/d
a = arccos(dx/d)
a = arccos(3/3.85) = 38.8°
Distance of fall from rest,
without air resistance = (1/2) (gravity) (time)²
= (1/2) (9.8 m/s²) (95 sec)²
= (4.9 m/s²) (9,025 sec²)
= 44,222.5 meters .
The depth of the mine shaft is five times the height of Mt. Everest !
