"Reflection" is the change direction of waves when blocked by obstacle
Answer:
How to Test Hypotheses
State the hypotheses. Every hypothesis test requires the analyst to state a null hypothesis and an alternative hypothesis. ...
Formulate an analysis plan. The analysis plan describes how to use sample data to accept or reject the null hypothesis. ...
Analyze sample data. ...
Interpret the results.
In an alpha decay, an atom emits an alpha particle. An alpha particle consists of 2 protons and 2 neutrons: this means that during this kind of decay, the original atom loses 2 protons and 2 neutrons from its nucleus.
This also means that the atomic number Z of the element (the atomic number is the number of protons in the nucleus) decreases by 2 units in the process, while the mass number A (the mass number is the sum of the number of protons and neutrons) decreases by 4 units.
