After the star's outer layers are expelled, the density of the remaining material is typically too low to provide adequate energy to sustain the hydrogen-burning shell's nuclear temperatures, and the remaining star easily contracts to form a white dwarf (a star with a density equal to the Sun, but a diameter equal to the Sun).
Answer:
The correct model is D.
Note: The first attachment below shows the different models. The second attachment shows the correct structural model of the water molecule.
Explanation:
A water molecule is composed of one atom of oxygen and two atoms of hydrogen.
A water molecule is polar, i.e. it contains positively and negatively opposite ends. The polar nature of the water molecule is due to strong electronegativity of oxygen which results in an uneven sharing of the bonding electrons between oxygen and hydrogen. The oxygen atom attracts the shared electrons more to itself, thereby, it acquires a partial negative charge, while the hydrogen atoms acquire a partial positive charge.
The bond angle between the oxygen and hydrogen atoms is approximately 105°. Therefore, from the first attachment below, the correct model for the water molecule is D.
The three chromosomal aberration:
1.) Inversion - breakage of chromosome in two places , the other piece of DNA is re- inserted into the chromosome.
2.) Translocation - the one piece breaks off and attaches to another chromosome.
3.) Deletion - the loss of segment of chromosome.
-ace
Drilling with pipe and mud
Explanation:
A cell's lipid bilayer allows to small uncharged substances such as: ions, hydrophobic molecules, oxygen and carbone dioxide to travel through the membrane by simple diffusion