What characteristic do photosynthesis and combustion share? 1.They both start with chemical energy.

2.They both involve chemical change.

3.They both occur in living organisms.

4.They both are endothermic.

D. They both involve chemical change.

Both photosynthesis and combustion are chemical changes. In photosynthesis, green plants produce their food in the presence of sunlight using carbon dioxide and water.

Combustion refers to something being burnt. It usually applies to burning of fossil fuels.

These processes are both chemical changes because:

- they are not reversible processes

- new products are formed.

- mass is conserved

- they require considerable amount of energy.

the transfer of heat by electromagnetic radiation is called thermal radiation . it is usually carried out by electromagnetic waves in an energy range just below the visible spectrum, which is the infrared range.

so the answer would be radiation.

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