C.............................
Answer:
93 billion light years
Explanation:
The proper distance—the distance as would be measured at a specific time, including the present—between Earth and the edge of the observable universe is 46 billion light-years (14 billion parsecs), making the diameter of the observable universe about 93 billion light-years (28 billion parsecs).
Answer:
A. Earth's tilt on its axis
Explanation:
Because of the earth's tilt, during part of the year the NE US is angled towards the sun, but the other part of the year it is angled away from the sun. This is what gives us our seasons.
Car fuels, adioactive plants, green house gases