<u>Answer:</u> The formula of the compound formed between rubidium and fluorine is RbF
<u>Explanation:</u>
Ionic bond is defined as the bond which is formed by complete transfer of electrons from one atom to another atom.
The atom which looses the electron is known as electropositive atom and the atom which gains the electron is known as electronegative atom. This bond is usually formed between a metal and a non-metal.
Rubidium is the 37th element of the periodic table having electronic configuration of 
This will loose 1 electron to form
ion
Fluoride is the 9th element of the periodic table having electronic configuration of 
This will gain 1 electron to form
ion
To form
compound, 1 rubidium ion is needed to neutralize the charge on fluoride ion
The formation of the given compounds is shown in the image below.

We know that
, where
is density,
is mass, and
is volume.
Substitute in the values we know and solve:

The answer would be option B "I believe there is life on other planets." Scientific statements have a possibility to be wrong. It's not option A because option A is a opinion. It's not option C because option C is a fact. It's not option D because option D is a opinion.
Hope this helps!
Answer:
the specimen has 11460 years old
Explanation:
if the live sample has as initial amount of Yo C14, the dead sample will have 0.25Yo of C14.
the rate of decay of radiactive matter over time is
- Y(t) = Yo * e (( - t * Ln2 ) / T)
∴ Y(t) = 0.25Yo; T = 5730
⇒ 0.25Yo = Yo * e (( - t * Ln2 ) / 5730 )
⇒ 0.25 = e (( - t * Ln2 ) / 5730 )
⇒ Ln(0.25) = ( - t * Ln2 ) / 5730
⇒ - 7943.466 = - t * Ln2
⇒ 7943.466 / Ln2 = t
⇒ t = 11460 year