If you define the ground as position zero and points above that to have positive altitudes, then the acceleration caused by gravity points in the negative direction. ... Gravity still acts in the downward direction. And the upward force from the floor is equal and opposite to your weight.
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The bulk of earths atmospheric oxygen comes from phytoplankton, small flower like things in the ocean.
The object shown is a convex mirror. A convex mirror has a reflective surface and the body of it is curved outwards, it is used in sunglasses, security areas, telescopes, and magnifying glass.