Science always begins with what?

Step 7- Communicate. Present/share your results. Replicate.

Step 1- Question.

Step 2-Research.

Step 3-Hypothesis.

Step 4-Experiment.

Step 5-Observations.

Step 6-Results/Conclusion.

answer; i believe the correct answer is (c) /// is a homogeneous mixture of gaseous substance nitrogen,oxygen and smaller amounts of other substancesmixtures can be either ( homogeneous or heterogeneous)plz check first good luck

the answer is 303.15 or 303