<u>Answer:</u> The mass of ice is 
<u>Explanation:</u>
We are given:
Area of Antarctica = 
(Conversion factor: 
)
Height of Antarctica with ice = 7500 ft.
Height of Antarctica without ice = 1500 ft.
Height of ice = 7500 - 1500 = 6000 ft = 
(Conversion factor: 1 ft = 30.48 cm)
To calculate mass of ice, we use the equation:
We are given:
Density of ice = 
Volume of ice = Area × Height of ice = 
Putting values in above equation, we get:
Hence, the mass of ice is
Answer:
D
Explanation:
Nitrogen is a naturally occurring element that is essential for growth and reproduction in both plants and animals. It is found in amino acids that make up proteins, in nucleic acids, that comprise the hereditary material and life's blueprint for all cells, and in many other organic and inorganic compounds.
Answer:
Electronegativity in group 1 decreases as we go from Lithium to Francium.
Explanation:
Electronegativity is defined as the tendency of an element to attract an electron pair towards itself.
In a group generally this tendency decreases from top to bottom as the size of the atom increases and hence the positive nucleus get far from the outer orbital.
In the same way group 1 elements i.e. from Lithium to Francium electronegativity decreases.
Answer: 1
Explanation: Lithium has a single electron in the second principal energy level, and so we say that lithium has one valence electron.
answer
When an electron temporarily occupies an energy state greater than its ground state, it is in an excited state. An electron can become excited if it is given extra energy, such as if it absorbs a photon, or packet of light, or collides with a nearby atom or particle
