If my math is right its A) 7
because 189 divided by 27 is 7
Eras and then smaller periods based on geologic and biologic events that occurred during those times. According to geological time scale, there are six eras from the beginning some periods of few eras & then period is classified into smaller units called "epoch"
In short, Your Answer would be Option B
Hope this helps!
It honestly depends. Fossil fuels are non-renewable so if reserves are depleting there is a threat of them running out and/or more pollution.
When the capacitor is connected to the voltage, a charge Q is stored on its plates. Calling 
the capacitance of the capacitor in air, the charge Q, the capacitance and the voltage (
) are related by
(1)
when the source is disconnected the charge Q remains on the capacitor.
When the space between the plates is filled with mica, the capacitance of the capacitor increases by a factor 5.4 (the permittivity of the mica compared to that of the air):
this is the new capacitance. Since the charge Q on the plates remains the same, by using eq. (1) we can find the new voltage across the capacitor:
And since 
, substituting into the previous equation, we find:
Ware them down, its like rubbing two pieces of chalk together.
