Given that,
Energy 
Surface temperature = 11000 K
Emissivity e =1
(a). We need to calculate the radius of the star
Using formula of energy
Put the value into the formula
(b). Given that,
Radiates energy 
Temperature T = 10000 K
We need to calculate the radius of the star
Using formula of radius
Put the value into the formula
Hence, (a). The radius of the star is 
(b). The radius of the star is 
2.85 x 10^2 (ten to the second power)
Answer:
6
6 significant digits
Explanation:
Number of significant digits of a number are the number of digits that carry a relevant contribution to the measurement.
For the case above;
104.100
rule - all digits to the right of the decimal of any number equal or greater than 1 will count as a significant digit.
104.100 --- .100 ( the three digits counts)
And since the the digits to the left are none zero digits, so they all count as significant digits.
104.100 --- 104 ( the three digits counts)
The total number of significant digits,
Since all the digits of the number 104.100 will count as a significant digit.
The number of significant digits is equal to the number of digits in the number.
N = 6
6 significant digits
You could use grams hope this helps
Answer:
you can learn from here
https://www.toppr.com/ask/en-bd/question/a-car-is-moving-with-a-velocity-of-10-ms-the-driver-sees-a-wall/
