Based on current estimates of the value of Hubble's constant, how old is the universe?
A) between 4 and 6 billion years old
B) between 8 and 12 billion years old
C) between 12 and 16 billion years old
D) between 16 and 20 billion years old
E) between 20 and 40 billion years old
Question 2
Which of the following is not considered a likely solution to the question of why we are not currently aware of a galactic civilization?
A) There is no galactic civilization because civilizations are not common.
B) There is no galactic civilization because civilizations do not leave their home worlds.
C) The galactic civilization is deliberately avoiding contact with us.
D) The galactic civilization probably is undetectable to us because it makes use of technologies that do not obey the known laws of physics.
E) There is no galactic civilization because most civilizations destroy themselves before achieving interstellar travel.
Examples of cell-to-cell communication based on the distance between cells
Female choice of males based on nuptial gifts.
Hubble’s Tuning Fork Diagram
The Universe According to Ptolemy, Second Century A.D.
Write equilibrium constant expressions for the following reactions in terms of concentration:
An electrochemical cell is based on these two half-reactions