4)
variables d and w
5d +1(4d)=36
9d=36
d=4 w=4x4=16
difference of price $12
5)
E 5 comics
F= 10
G=20
e+ (e+5) + 2(e+5)=35
e+ e+5 + 2e +10 =35
4e +15=35
4e=20
e=5
Eugene = 5 comics
6)
Agnes and Billy had each 300 (after drinking it will be less water)
A 300-200 =100
B 300-100 =200