Will give brainliest! the first known telescopes, used around 1600, consisted of a lens and an eyepiece. today, telescopes are often computer controlled and consist of a complicated array of sophisticated lenses. which statement correctly describes how telescopes have changed over time? a. the telescopes of the 1600s were used until the year 2000, when a more sophisticated telescope was built. b. the telescopes of the 1600s were gradually improved upon over time, resulting in the telescopes that are available today. c. the telescopes of the 1600s were used until the year 1900, when a more sophisticated telescope was built that was used until the year 2000. d. the telescopes of the 1600s were abandoned after about 50 years, and the technology was completely replaced.

It takes 945.kj/mol to break a nitrogen-nitrogen triple bond. calculate the maximum wavelength of light for which a nitrogen-nitrogen triple bond could be broken by absorbing a single photon.

Astudent made a graph plotting the progress of a reaction over time. the student forgot to label the y-axis of the graph. a graph is shown with two graph lines. one graph line starts at a higher position on the y axis and slopes downwards towards the right. the other graph line starts at a lower position on the y axis and slopes upwards towards the right. the two graph lines stop short of intersecting each other and continue as separate lines which gradually become straight and parallel to the x axis. a vertical line is shown at a point where the two graph lines finally became parallel to the x axis. this vertical line is labeled equilibrium. the title on the x axis is time and an arrow pointing towards the right is shown above time. the title on the y axis is left blank. what best explains the label that the student should use on the y-axis? amount, because as the amount of product decreases, the amount of reactant increases over time. reaction rate, because forward and backward reaction become equal at equilibrium. amount, because the amounts of reactants and products become constant after equilibrium is reached. reaction rate, as the rate of forward reaction increases and rate of backward reaction decreases over time.

The number to the right of an element's symbol (ex. c-12) identifies the of an isotope.