Guys i need asa 45 pointss!

which of the following could be a method used to order geological events? (3 points)

select one:
a. calculating the rate of weathering and erosion of rocks
b. comparing the minerals present in different strata of rock
c. calculating the radioactive decay rates on all known elements
d. using relative and absolute dating to find age of objects from the past

In this experiment, the was intentionally manipulated. it is the independent variable. the dependent variables that were measured were the

Ascience research group is testing a new type of plant food. one trial is conducted in a controlled experiment. the data from the trial show that the plant that received the new food grew faster than the control plant. the group announces that the new plant food makes plants grow faster. what is the main weakness in this scientific claim?

In an experiment examining the effects tai chi on arthritis pain, callahan (2010) selected a large sample of individuals with doctor-diagnosed arthritis. half of the participants immediately began a tai chi course and the other half (the control group) waited 8 weeks before beginning. at the end of 8 weeks, the individuals who had experienced tai chi had less arthritis pain that those who had not participated in the course.