Suppose that star x and star y both have redshifts, but star x has a smaller redshift than star y. what can you conclude?

here start X and star Y both have red shift which means they both will move away

Also star X has smaller red shift than star Y which means star X is moving slower as compare to start Y

Explanation:

When source of light move relative to an stationary observer then the change is frequency is given by the formula

also we can write it in terms of wavelength

so here if the source is moving away from the observer then the frequency of the light will decreased and hence the wavelength will increase

This effect is known as red shift and as per above formula it depends on the speed of the source

so here start X and star Y both have red shift which means they both will move away

Also star X has smaller red shift than star Y which means star X is moving slower as compare to start Y

half of a circle

explanation:

the arrow and the top of the circle is matching together. it is not a polygon because a polygon would always be the same shape. therefore, an half of a circle is called semicircle so you would find the radius of it.

answer: point c: b. 1/2 potential, 1/2 kinetic, point a: 3/4 of its potential energy, point d or b: 3/4 potential, 1/4 kinetic

explanation: i cant explain. it's difficult to explain.