Swihart chapter 6: #1 & #2

#6
F=F0*10^(-mag/2.5)
Ftotal=F0*(10^(-1/2.5)+10^(-1.5/2.5)+10^(-2/2.5))
mag combined=-2.5*log(Ftotal/F0)=-2.5*log(10^(-1/2.5)+10^(-1.5/2.5)+10^(-2/2.5))
* ? -2.5*log10(10^(-1/2.5)+10^(-1.5/2.5)+10^(-2/2.5))
    .2317603603889171    

fractions: 10^(-2/2.5)/(10^(-1/2.5)+10^(-1.5/2.5)+10^(-2/2.5))
* ? 10^(-2/2.5)/(10^(-1/2.5)+10^(-1.5/2.5)+10^(-2/2.5))
    .1962023225993320    
* ? 10^(-1.5/2.5)/(10^(-1/2.5)+10^(-1.5/2.5)+10^(-2/2.5))
    .3109597254327406    
* ? 10^(-1/2.5)/(10^(-1/2.5)+10^(-1.5/2.5)+10^(-2/2.5))
    .4928379519679275    

#8
m-M=5*log(r/10)
10^(1+(m-M)/5)=r
* ? 10^(1+(8.8-3.1)/5)
    138.0384264602885    !pc

M=4.77-2.5 log(L)
L=10^((4.77-M)/2.5)
* ? 10^((4.77-3.1)/2.5)
    4.655860935229588    !Lsun
res*Lsun=4 pi R^2 sigma T^4
sqrt(res*Lsun/(4*pi*7000^4*sigma))=R

* ? sqrt(res*Lsun/(4*pi*7000^4*sigma))
    1020655942.111505    !(m)
* ? res/Rsun
    1.467092054206562    !(Rsun units)

364t104.pdf #6, #8

#6
* ? -2.5*log10(10^(-1/2.5)+10^(-2/2.5))
    .6361488422267659   
m-M=5 log(r/10)
10^(1+(m-M)/5)=r
* ? 10^(1+(1-4.74)/5)
    1.786487574852051    ! (pc)

IF A has the luminosity of the Sun, but is twice as hot, its radius must be 1/4 Rsun
as R^2T^4=constant

#8
a 1
b 4
c 1
d 2
e max (m-M): 7
f I go with 3 even though its only II=bright giant, but its lots cooler (wiki: 84 Rsun)
  alternative:7 (wiki claims 77 Rsun)
g 8