Answer:
Measuring distances to stars through stellar parallax. Measuring distances to stars through the moving cluster method. Astronomers measure the temperature of a star by looking at the star's color and its spectrum. The apparent brightness of a star tells how bright it seems to us
Explanation:
Answer:
The answer would be Point of Reference.
In order to determine, whether an object has moved or not, a point of reference is required. The reference point is required to the measure the movement of the object, without a reference point the distance or displacement cannot be obtained. Hence, a reference point is very required to determine, whether the object has moved or not.
(Hope this helps) Sky
Answer: n=15.56moles
Explanation:
PV = nRT
where
P is pressure in atmospheres
V is volume in Liters
n is the number of moles of the gas
R is the ideal gas constant = given as (0.0821L -atm/k-mol
PV = nRT
n= PV/RT
n= (1.5 X 230)/ (0.0821 X 270)
n= 15.56 moles
2.B. Describe the difference between a reaction that occurs spontaneously and one that does not. Spontaneous chemical reactions release energy and use that energy to power itself; non-spontaneous chemical reactions need to absorb energy, which they can't absorb their own energy that they don't even have.
