Answer:
In other words, it is so old that it is difficult to imagine.
Explanation:
In this case, the simplest answer is the correct one. It's not about math or science; it's just what it is; the history of the universe is very hard to imagine because is humans haven't been in it for very long.
Im not 100% positive but I believe the answer would be metaphor
Vertical can be replaced by Upright
I think the answer may be water pollution.
water pollution > Water pollution<span> is the contamination of </span>water<span> bodies (e.g. lakes, rivers, oceans, aquifers and groundwater). This form of environmental degradation occurs when </span>pollutants<span> are directly or indirectly discharged into </span>water<span> bodies without adequate treatment to remove harmful compounds.
source: Wikipedia </span>
Answer:
<h3>Let <u>us </u> go for a walk. (we/us)</h3>
