Answer:
Y Q W Z X
Explanations:
The most reactive element is the element that will displace an element from it compound . The most reactive element will replace the less reactive element in it compound.
Q+ + Y Reaction occurs
Since the reaction occurs the element Y which is more reactive displaced element Q from it compound.
Q+W+ Reaction occurs
The reaction occurs, that means element Q replaces element w from it compound. Element Q is therefore more reactive than element W.
W+Z+ Reaction occurs
The reaction also occurs . This is an indication that element W replaces element Z in it compound. This means element W is very reactive than element Z.
X+Z+ No reaction
There is no reaction here. This is an indication that element X is less reactive than element Z. This is why element X can't displace element Y in it compound.
Answer:
scale. Mercury thermometers can be used to determine body, liquid, and vapor temperature.
Answer:
ptic fiber communication and satellite communication are the leading technologies which are revolutionizing the world of telecommunications. Both technologies have their advantages and limitations which make them suitable for certain type of applications. This article will provide an overview of optic fiber and satellite communication technologies and present a comparison of the features and related issues.
Optic Fiber Communication
Optic Fiber communication transmits information by sending pulses of light (using laser) through an optic fiber. The low signal loss in optic fibers and high data rate of transmission systems, allow signals with high data rates (exceeding several Gbps) to travel over long distances (more than 100 km) without a need of repeater or amplifier. Moreover, using wavelength division multiplexing (WDM) allows a single fiber to carry multiple signals (upto 10 different signals) of multi-Gbps transmissions. Optic Fiber communication offers extremely high bandwidth, immunity to electromagnetic interference, non-existent delays and immunity from interception by external means. In the 1980s and 1990s, the continents were linked together using undersea optic fiber bringing about a paradigm shift in the global telecommunications.
These advancements in optic fiber communication has resulted in decrease of satellite communications for several types of communications. For instance, transmission between fixed locations or point-to-point communications, where large bandwidths are required (such as transoceanic telephone systems) are made through optic fiber instead of using satellite communication. Optic Fiber communication is also used to transmit telephone signals, Internet communication, LAN (Gigabit LAN) and cable television signals.
Satellite Communication
Satellite communications use artificial satellites as relays between a transmitter and a receiver at different locations on Earth. Satellite systems allow users to bypass typical carrier offices and to broadcast information to multiple locations. Communications satellites are used for radio, TV, telephone, Internet, military and other applications. There are more than 2,000 satellites around Earth’s orbit, being used for communication by both government and private organizations.
Communication Satellites are LOS (line-of-sight) microwave systems with a repeater. These satellites rotate around the earth with the speed of earth and are known as geostationary satellites. The limitations of antenna size also limits focusing capability making the coverage for a single satellite transmitter very large. This makes satellite communication ideal for TV and radio services as the signal has to flow from a single point to many points in a single direction. The large distance of satellites from the earth (about 22,300 miles) results in delays which adversely effects two-way communication like mobile conversations. Low earth orbit satellites can be used for two-way mobile communication because less power is required to reach those satellites.
Explanation:
During nuclear fission, great amounts of energy are produced from____.
Answer: Out of all the options presented above, the one that completes the statement and makes it true, is answer choice D) very small amounts of mass. Nuclear fission power does not produce carbon and also produces 12% of the world's power.
I hope it helps, Regards.
Answer:
The outer core of the earth is liquid.
Explanation:
Seismic waves travel through the Earth at different speeds and are reflected and refracted diffracted differently as they encounter layers of different densities.
By analyzing these waves, they have concluded that there is an inner core of solid iron surrounded by a liquid outer core consisting of nickel and iron.
A is wrong. The Earth consists of several layers
C is wrong. Seafloor spreading is caused by the movement of tectonic plates away from each other.
D is wrong. The mantle is mostly solid rock.
