Suggest and explain a reason why the brake blocks on a bicycle need to be replaced from time to time

About 2% of our solar nebula consisted of elements besides hydrogen and helium. However, the very first generation of star systems in the universe probably consisted only of hydrogen and helium.

Which of the following statements correctly describes the models put forth by Ptolemy and Copernicus to explain the universe? A. The model developed by Copernicus was simpler and had less inconsistencies than Ptolemy's model. B.

Muscle cells are filled with specialized proteins that allow for contraction to occur. True False

In the first-order spectrum, maxima for two different wavelengths are separated on the screen by 3.40 mm. what is the difference between these wavelengths?

Which state of matter has the most kinetic energy? A) colloid B) gas C) liquid Eliminate D) solid

Can an object travel at the speed of light? Why or why not?

Determine the amount of potential energy of a 5 Newton's book that is moved to three different shelves on a bookcase. The height of the shelves is 1.0 meter, 1.5 meter, and 2.0 meter

Which atom is involved in giving your heart energy to beat? carbon gold oxygen iron

Which of the following is the most accurate statement concerning the properties of matter? a. they can be written as symbols b. they can be observed and measured c. they cannot be tested or verified d. they change with the amount of matter present

Danilo is sliding down a slide. What forces are acting on him as he slides