Use the drop-down menus to indicate the stage of technological design in which each action would occur. Establish criteria and prepare the initial design.
Redesign and retest as necessary.
Define a need and research related information.
Build and test a prototype

each chemical family is represented as a group or column on the periodic table. based on chemical properties, there are 6 types of chemical families. group 1 represents alkali metals, group 2 represents alkaline earth metals, groups 3 to 12 represent transition metals, groups 13 to 16 represent non-metals and other metals, group 17 represents halogens and group 18 represents noble gases.

diaria maybe go see a doctor about that