User: The greenhouse effect is a result of A. absorption and radiation of energy in the hydrosphere. B. consumption of fruits and vegetables that produce a biofuel. C. absorption and radiation of energy in the atmosphere.
A principal focus or focal point is a special focus: 1  For a lens, or a spherical or parabolic mirror, it is a point onto which collimated light parallel to the axis is focused. Since light can pass through a lens in either direction, a lens has two focal pointsâone on each side.
If ever a need arises for an absolute example for what Peters and Waterman called âStick to the Knittingâ and Hamel and Prahalad termed core competence, one needs to look no further than Bill Gates and Microsoft. Focus also means the ability to pursue oneâs goals whatever the obstacles may be.