This is an example of observational study, because the biologist is not interfering or interacting with the subjects of study but just watching and registering data (recording with cameras).
The biologist is not conducting an experiment because (he is not setting up special conditions to register different responses to drive conclusions), and the biologist is not making any survey (questionnaires for example).
Answer: observational study
Answer:
0.67
Step-by-step explanation:
2 sandwiches / 3 brothers equal to 0.6 repeating which rounds to 0.67
Answer:

Step-by-step explanation:
y - 5 = 3⁄2(x + 6)
y - 5 = 3⁄2x + 9
+ 5 + 5
__________
y = 3⁄2x + 14
- 3⁄2x - 3⁄2x
________
−3⁄2x + y = 14 [We do not want mixed numbers\fractions in our standard equation, so multiply by the denominator to get rid of it.]
−2[−3⁄2x + y = 14]

I am joyous to assist you anytime.