3. the cause and the assumptionSetup problem1. coconut shell lamp more or less efficient lamps in the market or not.The assumption of 1. If the coconut shell lamp affect energy efficiency depends on the object of the lamps.
3. The assumption and the problem first. Product Focus efficient More or less all the lamps in the market? The first hypothesis. If the lamp Coconut affect energy efficiency. Depending on the material of the lamp.
3. Causes and hypothesis.The set problem.1. Coconut shell lamp efficiency. More or less a lamp in the market?The hypothesis, 1. If the coconut shell lamp on energy saving based on the object of the lamps.