Answer: Stars are formed in clouds of gas and dust, known as nebulae. Nuclear reactions at the centre (or core) of stars provides enough energy to make them shine brightly for many years. The exact lifetime of a star depends very much on its size.
Explanation: I try to do your question, hope this help
Answer:
Part a)
part b)
Part c)
Part d)
here since wave is moving in negative direction so the sign of 
must be positive
Explanation:
As we know that the speed of wave in string is given by
so we have
now we have
now we have
Part a)
= amplitude of wave
part b)
here we know that
so we have
Part c)
Part d)
here since wave is moving in negative direction so the sign of must be positive
Answer: Cells have receptors because Receptors let the cell know when to let things in and out of the cell.
Explanation:
Cell receptors also called transmembrane receptors are proteins located on the surface of a cell (extracellularly) or inside the cell which receive signals that alters the functions of the cell. The functions of the cells which can be altered includes the alteration in gene transcription and the cell morphology.
Cell receptors are generally categorizes into the following groups:
--> Internal receptors
--> cell surface receptors
--> ion channel receptors
--> G protein coupled receptors
--> enzyme linked receptors
Interaction of cell membrane receptors with specific ligands that bonds to the receptors causes conformational changes in the receptor protein. This in turn, enzymatically activates the intracellular part of the protein or induces interactions between the receptor and the proteins in the cytoplasm that act as second messengers, thereby relaying the signal from the extracellular part of the receptor to the interior of the cell. This enables the cell to know when to let things in or out of it through the information conveyed.
The most accurate weather for the next two days would be dry warm weather or severe thunderstorms if there is an occluded front over the area.
<u>Explanation:</u>
The weather front that is created during the cyclogenesis process is an occluded front in meteorology. Cyclogenesis process is the development of extra-tropical cyclone and its intensification.
During the occurrence of this, the warm air is occluded (separated) from the center of cyclone at the surface of the earth.
The cold front rotates the storm as it intensifies and holds up the warm front. This develops an occluded front, that is the boundary which separates the new cold air mass and the older cool air mass that is already in warm front's north.
Answer:
398.3 m, 334.2 m
Explanation:
The magnitude of the displacement vector is
v = 520 m
And its direction is
measured as north of east.
The x-component of this vector is given by:
While the y-component is given by
