If you hold out your thumb at arm's length and rapidly blink each ...

[RODY.ELKHALIL]

If you hold out your thumb at arm's length and rapidly blink each eye closed in an alternating pattern, your thumb appears to move left and right. This exercise is an example of _____________.
 
  Fill in the blank(s) with correct word

Question 2

Unseen objects in our galaxy have been found by the bending effect they have on more distant stars' light passing near them. These small objects that don't emit light are calculated to have masses of about 10 the mass of the Sun. Which is the best choice for these objects?
 
  a. black hole
  b. neutron star
  c. white dwarf
  d. main-sequence stars

[fwbard]

Answer to Question 1

parallax

Answer to Question 2

a
RATIONALE: Hint: Rank the objects by size, then add the mass.

[RODY.ELKHALIL]

Thanks for the timely response, appreciate it

[xiaomengxian]

Gracias!