What is the dangers of Global Variables in Drupal specifically?

What are the variables in this experiment?

• reacting copper,iron, magnesium, zinc and aluminium with 25ml of copper sulphate then measuring the peak temperature: what are the: independent variables dependent variables control variables categoric variables continuous variables what stuff in the experiment will be which variable?

• Answer:

  Independent variable - this is the thing you change, so in this case it would be the element: copper,iron, magnesium, zinc and aluminium. Dependent variable - this is the thing you measure, so it would be peak temperature. Control variables are variables you control, like amount of copper sulphate, amount of elements you are using, starting temperature, etc. Categoric variables- these are variables you can put into categories, so I guess it would be the elements you are using but I'm not 100% sure. Continuous variables - variables that can have any value, e.g. decimals. This would be your peak temperature as you could have 10.5 degrees for example, not just whole numbers. Hope this helps!