The relationship between the resistance R of a wire and its resistivity

is given by

where L is the length of the wire and A is its cross sectional area.
In the problem, we have

,

and

. So we can solve the find the area A:

For a cylindrical wire, the cross sectional area is given by

where r is the radius. We know the value of the area A, so now we can find the radius of the wire:
(a) The time for the capacitor to loose half its charge is 2.2 ms.
(b) The time for the capacitor to loose half its energy is 1.59 ms.
<h3>
Time taken to loose half of its charge</h3>
q(t) = q₀e-^(t/RC)
q(t)/q₀ = e-^(t/RC)
0.5q₀/q₀ = e-^(t/RC)
0.5 = e-^(t/RC)
1/2 = e-^(t/RC)
t/RC = ln(2)
t = RC x ln(2)
t = (12 x 10⁻⁶ x 265) x ln(2)
t = 2.2 x 10⁻³ s
t = 2.2 ms
<h3>
Time taken to loose half of its stored energy</h3>
U(t) = Ue-^(t/RC)
U = ¹/₂Q²/C
(Ue-^(t/RC))²/2C = Q₀²/2Ce
e^(2t/RC) = e
2t/RC = 1
t = RC/2
t = (265 x 12 x 10⁻⁶)/2
t = 1.59 x 10⁻³ s
t = 1.59 ms
Thus, the time for the capacitor to loose half its charge is 2.2 ms and the time for the capacitor to loose half its energy is 1.59 ms.
Learn more about energy stored in capacitor here: brainly.com/question/14811408
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Answer: B. Rhyolitic
Rhyolitic magma is responsible for most violent volcanic eruptions. Rhyolitic magma erupts catastrophically with high intensity gas content. This magma being more viscous traps gases, builds pressures and erupts explosively. High viscosity of this magma is because of high silica content that erupt with the mineral contents of the rocks.