In the given case, Adeline is probably to get scared and shocked regarding menarche as the culture of her time did not assist in educating young women about menarche.
Menarche refers to the initiation of the menstrual cycle, or first menstrual bleeding, in females. From both the medical and social point of view, it is usually regarded as the principal incident of female puberty, as it indicates the probability of fertility.
Although the dolphin lives in the sea, it is not a fish - it's a mammal.
It makes the most sense if you read it aloud.
The type of microscope that <span>can produce three-dimensional images of a cell’s surface is the electron-scanning microscope. In this type, beam of high-energy electrons is focused to project the correct projection of the cells. The projection of the cells are made up of signals of the surface.</span>
A measurement of population per unit area
For example x amount of people in 1000 square feet