The double helix is a description of the molecular shape of a double-stranded DNA molecule. In 1953, Francis Crick and James Watson first described the molecular structure of DNA, which they called a "double helix," in the journal Nature.
Answer:
At sea level, air pressure is greatest because it is caused by the weight of the entire column of atmosphere at that altitude over that location. As altitude increases, the column of atmosphere gets shorter, and so less weight is pressing down at a given altitude, so atmospheric pressure is reduced.
The sewing needle should float in the water if placed on a horizontal angle if I remember properly.
I hope this helps in some way.
The right answer here is option C. They occur in areas with ancient, mineral-poor soil.
An example of that is Amazonia in Brazil, it's one of the biggest forests on earth, and at the same time, we know its soil is poor, but at the same time it has some special materials that can be found there, such as niobium. This forest is, too, rainy almost all the time, and this many trees maintain the temperature of the whole earth stabilized. These kinds of forests can grow in this soil because of the burlap, that's organic materials from its own trees. It's consumed by them, and through this way, it survives and extends its size when humans don't use its resources too much.
The substances they need are carbon dioxide, water, and chlorophyll, and the substances produced by photosynthesis is 1 glucose molecule and 6 oxygen molecules