These are marked through response marking and how the student formats their answer. You need to state two points and elaborate upon them to achieve full marks. For example: explain how global warming can be caused. An increasing world population is resulting in a higher demand for energy (stated point). This energy requires burning more fossil fuels sending CO2 up into the atmosphere causing it to trap heat (developed point)Also, as countries get richer they demand more products (stated point). As more factories are making more products CO2 is released into the atmosphere and traps more heat (developed point).Basically, it's about developing your initial statements by linking them directly back to the question.