Answer:
Option (2)
Explanation:
Strato-volcanoes are the steep, conical shaped, formed by the alternative beds of ash and lava. The magma in this type of volcano contains high silica content and are comprised of bubbles. When the gases are released from these bubbles, then a greater force is exerted from the bottom towards the surface. Due to this, they are very explosive and ejects a huge amount of materials during eruption. For example, Mount St. Helens
.
Cinder cones are the simplest volcanoes with steep sides. They are made of the materials and semi solidified lava that are ejected from the vents of the volcano. Eruptions are often explosive due to the force exerted by the gas and the molten lava and are accumulated near the vent. For example, Paricutin.
<u>These two types of volcanoes are similar in terms of its eruption that is violent and explosive in nature. In addition to that, they both have steep sides.
</u>
Hence, the correct answer is option (2).
Fuel cells can make an electricity from a simple electrochemical
reaction in which oxygen and hydrogen combine to form water. There are several
different types of fuel cell but they are all based around a central design
which consists of two electrodes, a negative anode and a positive cathode.
These are separated by a solid or liquid electrolyte that carries electrically
charged particles between the two electrodes. A catalyst, such as platinum, is
often used to speed up the reactions at the electrodes. Fuel cells are
classified according to the nature of the electrolyte. Every type needs
particular materials and fuels and is suitable for any applications. The
article below uses the proton exchange membrane fuel cell to illustrate the
science and technology behind the fuel cell concept but the characteristics and
applications of the other main designs are also discussed. Proton Exchange Membrane Fuel Cells (PEMFC)
The hydrogen ions permeate across the electrolyte to the
cathode, while the electrons flow through an external circuit and provide
power. Oxygen, in the form of air, is supplied to the cathode and this combines
with the electrons and the hydrogen ions to produce water. These reactions at
the electrodes are as follows:
Anode: 2H24H+ + 4e-
Cathode: O2 + 4H+ + 4e- 2H2O
Overall: 2H2 + O22H2O + energy
PEM cells operate at a temperature of around 80°C. At this
low temperature the electrochemical reactions would normally occur very slowly
so they are catalysed by a thin layer of platinum on each electrode.
Explanation:
A correct father is identified through the current techniques for paternity testing are using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP).
A suspect is identified using a small sample of evidence forensic DNA analysis
Forensic DNA analysis usually involves comparisons between genetic profiles extracted from biological samples collected from a specific site, object or person which is thought to be associated to a crime, in order to determine the likelihood that such samples come from a particular person
A missing person is correctly identified by
Efficient Face Recognition System for
Identifying Lost People
Answer:Bisexual flowers are complete flowers, containing both androecium and gynoecium in one flower. Therefore, bisexual flowers contain both stamens and pistils in the same flower. Hence, bisexual flowers are called hermaphrodite or androgynous flowers as well.
Explanation:
The age of oceanic bedrock on either side of a mid-ocean ridge is supporting evidence that at the ridges, tectonic plates are Diverging
.
Explanation:
The underwater mountain range is the mid oceanic ridge, which were formed as a result of plate tectonics. when the convection current goes up in the mantle present beneath the oceanic crust results in the uplifting of the ocean floor.
Which leads to the formation of the tectonic plates through magma, that meet at divergent boundaries. The density and the age and the thickness of these oceanic crust increases due to the distance from the ridges. The mid oceanic ridges has been split on two sides as matching stripes
,
