Most of them seem like opinions and questions. although I’m not certain I would confidently go with “Experimenting with moldy bread more fun than experimenting with yogurt cultures?”
Answer:
The control group consists of elements that present exactly the same characteristics of the experimental group, except for the variable applied to the latter. This group of scientific control enables the experimental study of one variable at a time, and it is an essential part of the scientific method.
Apply high pressure to the rock. Apply high temperature to the rock. Apply high temperature and pressure to the rock.
The half-life of carbon-14 is equal to 5730 years. The amount of substance with half-life h at any time t is equal to,
At = (Ao) x (1 - 0.5)^(t/h)
Substituting,
At/Ao = 0.67 = 0.5^(t/5730)
The value of t from the equation is 3310.6 years.