<span>d. 93 billion miles
</span>Earth, being the third planet from the sun is unique in the universe because it is currently the only planet known to support life. Earth's distance from the sun is really one of the key reasons why it is has widespread life.Earth occupies what scientists sometimes call the Goldilocks zone. Its distance from the sun means its neither too hot nor too cold to support liquid water. Water is thought to be a key ingredient for life.<span> The energy from the sun in just the right intensity and the availability of water on the earth make it possible for life to thrive on earth. Plants use both these resources for photosynthesis and make nutrients that are available to support the life of animals on the earth. </span>
Conserve natural resources, energy and landfill space.
Via half-life equation we have:

Where the initial amount is 50 grams, half-life is 4 minutes, and time elapsed is 12 minutes. By plugging those values in we get:

There is 6.25 grams left of Ra-229 after 12 minutes.
Explanation:
Displacement=Velocity×time
=24.7×16.00
=395.2m
Therefore the displacement within the time interval is 395.2m
The candle is giving off light
Chemical energy from the candle is converted to thermal energy