Answer;
-Noble gases or Group 18 elements
Explanation;
A full valence shell is the most stable electron configuration. Group 18 elements or noble gases such as helium, neon, and argon, have a full outer, or valence, shell. Elements in other groups have partially-filled valence shells and gain or lose electrons to achieve a stable electron configuration.
They are extremely unreactive and do not form bonds with themselves. Solid helium is the the ultimate fine powder being monotomic.
Answer:
When the rule of 70 applies to population, dividing 70 by the percentage of population growth should equal the time (in years) that the population needs to be double (option A)
Explanation:
The rule of 70 is useful to calculate the time in which a variable of any type can be duplicated. The calculation is done by dividing the number 70 by the percentage of growth of the variable.
<u>If the rule of 70 is applied to the population, it is possible to calculate, based on its growth rate, the time that population would need to double</u>.
If, for example, the growth rate of a population is 3 percent:
70 / 3 = 23,33
This indicates that a population, with a growth rate of 3% would need about 23,33 years to double.
Answer:
B. The prefixes chemo- and photo-: define the electron source
Explanation:
The prefix chemo is related to <u>chemical/drug</u> and photo is related to<u> light</u>. This can be proved by analysing the following examples:
Chemotherapy = therapy with chemicals
Phototherapy = therapy with light
Answer: S waves
Explanation:
After an earthquake, secondary waves arrive second at a seismometer. Secondary waves, or S waves, are seismic waves that are known as body waves.
