This can be done by absolute dating technique. In this, the amount of radioactive material with a known half-life is measured. The measure of the radioactive decay of the elements present in the rock helps in the back calculation of the age of the rock. For older rocks, isotopes of Beryllium, Uranium, Argon etc. are used.
The correct answer is - C and D.
The principle of original horizontality means that the rock layers have been order by age, with the layers at the top being the youngest, while the layers at the bottom being the oldest.
In this picture it is little hard to tell which rocks belong to the same layer from first look because there are multiple twists and turns, an uneven surface, caused by pressure on the crust.
By carefully examining the image though, we can trace the layers more properly and see which ones are younger, which older, and which have the same relative age. In this case, we can see that the markings C and D are actually on the same layer of rocks, thus being a good indication that they have the same relative age.
Answer:
B. cardiac cells, which are a type of muscle cell
The genotype of a normal male zygote is XY, with the X chromosome (sex chromosome) coming from the mother and Y from the father.
This patient both has left-sided heart failure and right-sided heart failure. In left-sided heart failure, this patient exhibits increasing shortness of breath on exertion as well as three pillow orthopnea which indicates pulmonary congestion. This is because of pooling of blood in the pulmonary circulation. Bipedal edema, in this patient is a grade 2 bipedal edema, reflect right-sided heart failure as there is pooling of blood in the systemic circulation, causing transudation in the most dependent areas of the body.
