Answer:
105 m/s
Explanation:
Given that the speed of train A, 
= 45 m/s from west to east.
Speed of train B, 
= 60 m/s from east to west.
Train B is moving in the opposite direction with respect to the speed of train A. Assuming that the speed from east to west direction is positive.
So, the speed of train A from east to west= - 45 m/s
The speed of train B w.r.t train A 
m/s
Hence, the speed of train B w.r.t train A is 105 m/s from east to west.
The gravitational force between two objects is given by:
where
G is the gravitational constant
m1 and m2 are the masses of the two objects
r is the separation between the two objects
The distance of the telescope from the Earth's center is
, the gravitational force is
and the mass of the Earth is
, therefore we can rearrange the previous equation to find m2, the mass of the telescope:
Extinct<span> might be a word you associate with animals that lived long ago, like the dinosaurs, but did you know that over 18,000 species are classified as "threatened" (susceptible to extinction) today? Scientists involved in wildlife conservation have a tough job; they are in charge of determining what needs to be done to prevent a species from becoming extinct. Habitat, food supply, and impacts of local human populations are just a few of the factors these scientists take into account. It is a lot to keep track of for a single location, but the job becomes even harder when it is a migratory animal. In this science project, you will get a firsthand look at their job. You will access </span>real<span> data about migratory birds and use satellite images to analyze their habitats, then come up with a conservation plan to protect the species from extinction.</span>
Answer:
The state of a certain type of land or a biome.
Answer:
human cheek cell has got a nucleus, rbc doesnot
human cheek cell is found in the cheeks n made there whereas rbc is made in the bonemarrow and found in blood
human cheek cell serves the function of supplying nutrition to cheek by simply exchange while rbc transports oxygen around the body..
cheek cell can reproduce rbc cannot asit is non nucleated.The epithelial cells in the lining of the mouth are referred to as basal mucosa and divide roughly every 24 hours. They can easily be obtained through a simple swab or a mouth rinse. The cheek cell is very simple, but it contains the entire genetic makeup of the person's body. For this reason, cheek cells are frequently used to establish paternity and other investigations involving DNA. More recently, researchers have discovered that the cheek cell can be used to measure a person's likelihood of having high blood pressure.
A human cheek cell is thin, flat and irregularly shaped and has a large nucleus that contains the DNA. Its plasma membrane helps the cell to maintain suitable temperature while giving it its shape. Since it is selectively permeable, it only allows certain molecules into and out of the cell. Its cytoplasm contains water that dissolves nutrients and enzymes. It is an animal cell so it is different from plant cell.and the difference will be same as that with animal cell
