Answer:
(a) 
(b) P = 0.816 Watt
Explanation:
(a)
The power radiated from a black body is given by Stefan Boltzman Law:

where,
P = Energy Radiated per Second = ?
σ = stefan boltzman constant = 5.67 x 10⁻⁸ W/m².K⁴
T = Absolute Temperature
So the ratio of power at 250 K to the power at 2000 K is given as:

(b)
Now, for 90% radiator blackbody at 2000 K:

<u>P = 0.816 Watt</u>
The specific answer for that will be 71.38 kg
Well let’s put it this way. To find the neutrons you subtract the atomic atomic Nuremberg from the atomic mass. So
Mass=81-Number=28
81-28=53
Final answer is 53.
Both verbs come from Olde English.
That's why everybody clearly understood their meaning until
a hundred years ago, but nobody understands them now.
"Waxing" = growing
For two weeks after the New Moon, it's growing toward Full.
First it's a waxing crescent for a week, then it's waxing gibbous.
"Waning" = shrinking
For two weeks after the Full Moon, it's shrinking toward New.
First it's waning gibbous for a week, then it's a waning crescent.
Answer:
quark
Explanation:
neutrón= 1.675 x 10-27 kg
proton=1,673 x 10-27 kg
electron=9,11 x 10-31 kg
quark=7,13 - 14,26 · 10−30 kg