Question

1. select all that apply.

select three things needed to start and spread a fire.
oxygen
fuel
wind
a heat source
carbon dioxide

Explanation:

To start and spread a fire, the three essential components (fire triangle) are fuel, oxygen, and a heat source. Wind can help spread fire by providing oxygen and moving embers, but the core requirements for ignition are fuel, oxygen, and heat. Carbon dioxide is a fire suppressant, not a fire starter. So the three needed are a heat source, fuel, and oxygen (wind can aid spread but the question asks for "needed to start and spread"—the core three for ignition, and wind can aid spread, but typically the fire triangle is fuel, oxygen, heat; however, the options here include wind as a spread aid. Wait, re - evaluating: The fire triangle (start) is fuel, oxygen, heat. To spread, wind can help. But the question says "needed to start and spread". So fuel (needed to start), oxygen (needed to start), a heat source (needed to start), and wind (needed to spread). But the question says "select THREE". Wait, maybe the intended three are a heat source, fuel, and oxygen (the fire triangle for starting, and wind for spreading, but maybe the question considers wind as a spread factor and the three core for start and spread include wind? Wait, no—let's check the options. The options are oxygen, fuel, wind, a heat source, carbon dioxide. Carbon dioxide is out. So the three needed: fuel (to burn), oxygen (oxidizer), a heat source (to ignite), and wind helps spread. But the question says "select THREE". Wait, maybe the answer is a heat source, fuel, and oxygen (the fire triangle) as the base, and wind as a spreader. But the question says "needed to start and spread". So the three are a heat source, fuel, and oxygen (for starting) and wind for spreading. But the question says "select THREE". Wait, perhaps the intended answer is a heat source, fuel, and oxygen (the three elements of the fire triangle, which are necessary to start, and wind helps spread but the three core for start and spread's base).

Answer:

a heat source, fuel, oxygen (the checkboxes for "a heat source", "fuel", and "oxygen" should be selected)