Why is an engineer an applied scientist?

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 type of organism is missing from the food web seen in the illustration? primary consumers decomposers primary producers secondary consumers

What is the answer for the complicated molecules that make up living things usually contain carbon. why is carbon so important in these molecules?