Answer:
A. The set of happy people.
B. The set of good teachers.
C. The set of enjoyable subjects.
D. The set of Philippine Presidents
Let named variables as you said g- guinea pigs and c- chinchillas
System of equation is:
First is: c+ g = 60,005
Second is: c= 2g+5
When we replace second in first we get:
2g+5+g = 60,005 => 3g+5= 60,005 => 3g= 60,000
g=60.000/3 = 20,000 => g=20,000
When this result we replace in the second equation we get
c= 2 * 20,000 +5= 40,000+5 = 40,005
c= 40,005
Good luck!!!!
2, 3, 5. I just solved them and they look equivalent.