Pick from:
(1). Firecrackers;
(2). breathing;
(3). burning fuel;
(4). eating food;
(5). warmth;
(6). condensing fuel;
(7). Green beans;
(8). cigarettes;

Fact 1: Fire converts chemical energy into light and heat energy. Fact 2: Fire needs fuel to burn. Given the two facts above, what converts chemical energy into light and heat energy?
Answer:
(3).