I think it is b cause I don’t think you do that
-- Conserve. Don't use more than we need. There isn't any more of it.
-- Conserve. Don't pollute what we have. There isn't any more of it.
Of course, what we REALLY need to do is <u><em>convince</em></u> great numbers of people to go along with these suggestions. Otherwise it won't work.
A - a child sliding down a water slide :)
Most likely, the equation is
<em>Acceleration over a period of time = </em>
<em>(change in speed during the period of time)</em>
<em>divided by</em>
<em>(length of the period of time) .</em>
for any piece of the graph.
About 5.67 × 10^20 in 2013 which is still about the same but a little higher in 2018 and 2019