Answer: 65000 seconds
Explanation:
Given that,
Current (I) = 2 mA
(Since 1 mA = 1 x 10^-3A
2 mA = 2 x 10^-3A)
Charge (Q) = 130 C
Time taken for a fully charged phone to die (T) = ?
Recall that the charge is the product of current and time taken.
i.e Q = I x T
130C = 2 x 10^-3A x T
T = 130C / (2 x 10^-3A)
T = 65000 seconds (time will be in seconds because seconds is the unit of time)
Thus, it will take a fully charged phone 65000 seconds to die
Without the ability to measure, it would be difficult for scientists to conduct experiments or form theories. Not only is measurement important in science and the chemical industry, it is also essential in farming, engineering, construction, manufacturing, commerce, and numerous other occupations and activities.
Answer: 
Explanation:
We know the total diameter of the cell (assumed spherical) is:

Then its total radius 
On the other hand, we know the thickness of the cell wall is
and its density is the same as water (
).
Since density is the relation between the mass
and the volume
:

The mass is:
(1)
Now if we are talking about this cell as a thin spherical shell, its volume will be:
(2)
Where 
Then:
(3)
(4)
Substituting (4) in (1):
(5)
(6)
Knowing
and
: