Question

1. choose the best answer.

stars are made of ______ and create light through nuclear fusion.
○ hydrogen and helium
○ sulfur and hydrogen
○ carbon and oxygen
○ silicon and phosphorous

1. choose the best answer.

the heat and light of the sun make ______ possible on earth.
○ the atmosphere
○ rotation
○ life
○ oceans

Explanation:

Question 14

Stars are primarily composed of hydrogen and helium. Nuclear fusion in stars mainly involves hydrogen fusing into helium, which produces light and energy. The other options (sulfur & hydrogen, carbon & oxygen, silicon & phosphorous) are not the main components of stars.

The sun's heat and light are essential for supporting life on Earth, as they drive photosynthesis, regulate climate, and provide energy for ecosystems. The atmosphere exists due to Earth's gravity, rotation is a planetary motion, and oceans form from water accumulation, not directly from the sun's heat/light in this context.

Answer:

A. hydrogen and helium

Question 15