Answer: 14 Explanation: Mass number: the total number of protons and neutrons in a nucleus.
Mass number = Protons + Neutrons
=
6
+
8
=
14
You haven't attached any options but anyways, to help you with your question, elements belonging to the same group (e.g. alkali metals, noble gases) all have the same chemical properties. Hydrogen, for example, have the same properties with Sodium, Potassium and Lithium.
The temperature when ice melts is 32 degrees Fahrenheit.