Astronomers have developed several ways to measure the vast distances between Earth and the stars and galaxies. What do you know about two of these techniques?
An astronomical unit (A. U.) is the average distance between the Earth and the Sun.
Our galaxy, the Milky Way, is about 150 light-years across
An astronomical unit is about 93 million kilometers.
Astronomers measure distances to objects which are outside our solar system in light-years.
The A. U. is used to measure distance within our solar system.
A light-year (ly) is the distance that light can travel in one year in a vacuum.

The table lists pressure and volume values for a particular gas. which is the best estimate for the value of v at p = 7.0 × 103 pascals?

Schrodinger and heisenberg developed an alternate theory about atomic nature that contradicted some of bohr's model of the atom. how do changes resulting from new technology and evidence affect the reputation of the atomic theory?

The scheme below is from a series of reactions that are part of a synthesis of vitamin a. answer the following questions with reference to this scheme. (i) what is "reagent a"? (ii) draw a step-by-step mechanism which explains the formation of compound c from compound b (iii) which reagents would you use to form compound e from compounds c and d (reagents b and c)? for each reagent suggested above in (ii) explain the role of the reagent in the reaction to (iv) form compound e. you may wish to do this by drawing a mechanism. 1. addition of reagent a но reagent a 2. н,о" thо oh нон-с compound a. compound b. compound c .ch-оh 1. reagent b "сно 2. reagent c сh oh compound e. compound d.