Answer as temperature increases, density: decreases increases remains the same

Why do astronauts in the space shuttle weigh less?

Which of the following list the divisions of the geologic time scale in order from longest to shortest

Does the distance travelled by an oscillating mass between times t=0 and t2 equal the displacement of the particle over the same time period if t2> t/2? hint: consider a sine wave starting at t1=0, then consider a closing wave starting at t1=0, for your explanation.