If the gradient or slope is high then the water flow will go faster because suppose water is flowing down from a skateboard ramp, it would flow faster than water flowing throw a straight pipe.
Here's a picture I drew to help you!
The answer is there (3). This is because a mitochondrion has it own DNA called mitochondrial DNA. Therefore the three genetic materials from different parents (mitochondria from donor mother, DNA from biological mother and DNA from biological father) would be present in the baby. Somatic nucleus transfer is the medical procedure used when the biological mother has mitochondria disorder which she would not wish to pass to her offsprings (which are inherited maternally).
Oak trees need nitrogen or carbon dioxide to live but because they don’t need oxygen the tree will release it to the world for the human to breathe