The ratio of the circumference of any circle to its diameter is . ...

[cartlidgeashley]

The ratio of the circumference of any circle to its diameter is . Similarly, the ratio of the energy of any photon to its frequency is
 
  1) h, Planck's constant,
  2) uncertain, unlike ,
  3) the wavelength of the photon,
  4) c, the photon's speed,
 
  which is
  5) a basic constant of nature setting a lower limit on the smallness of things.
  6) a basic constant of nature setting an upper limit on the speed of things.

Question 2

The thing that is different between x-rays and radio waves is
 
  1) their charges,
  2) their masses,
  3) their frequencies,
  4) the medium through which they travel,
  5) the speeds at which they travel,
 
  and the thing that is the same for x-rays and radio waves is
  6) their masses.
  7) their frequencies.
  8) the medium through which they travel.
  9) the speeds at which they travel.
  10) none of these.

[Ashley I]

Answer to Question 1

Answer: 1, 5

Answer to Question 2

Answer: 3, 9

[cartlidgeashley]

Thank you!

[Ashley I]

Always glad to help...