Answer:
When a cold front overtakes a warm front, it creates what's called an occluded front that forces warm air above a frontal boundary of cooler air masses.
Explanation:
The presence of a cold front means that cold air is advancing and pushing underneath warmer air. This is because the cold air is ‘heavier,’ or denser, than the warm air. Cold air is thus replacing warm air at the surface.
E=hv is an equation important when dealing with light. E refers to the energy of a photon; h is Planck's constant and v is the wavelength. According to this equation, light particles called photons travels in packets of energy. This is important in pv cells because this is the technology used to harness solar energy which is converted to electricity. The amount of energy should be estimated to know the appropriate material of construction of the pv cell to achieve optimum conditions. In this way, the pv cell could maximize the sun's energy.
Polymerization would be the answer you're looking for.
D. Cyanobacteria one of the first beings
The right answer is polarity.
In chemistry, polarity is a characteristic describing the distribution of negative and positive charges in a dipole. The polarity of a bond or a molecule is due to the difference in electronegativity between the chemical elements that compose it, the differences in charge that it induces, and to their distribution in space. The more the charges are distributed asymmetrically, the more a bond or molecule will be polar, and conversely, if the charges are distributed in a completely symmetrical manner, it will be apolar, that is to say non-polar.
Polarity and its consequences (van der Waals forces, hydrogen bonding) affect a number of physical characteristics (surface tension, melting point, boiling point, solubility) or chemical (reactivity).
Many very common molecules are polar, such as sucrose, a common form of sugar. The sugars, in general, have many oxygen-hydrogen bonds (hydroxyl group -OH) and are generally very polar. Water is another example of a polar molecule, which allows polar molecules to be generally soluble in water. Two polar substances are very soluble between them as well as between two apolar molecules thanks to Van der Waals interactions.