Models need to be changed when .

According to the law of conservation of energy, energy can neither be created nor destroyed. if this is true, why is there less energy in the top of the energy pyramid than there is in the bottom of the energy pyramid?

Which properties describe all matter?

'which of these statements about the scientific method is not true? all experiments must follow the same number of steps in the procedure. experiments may be repeated several times. some unexpected results can be beneficial. experimental results may or may not support the hypothesis.