for one it would be rising and for two dropping
Sponges are in the Porifera phylum
Bacteria Growth Rate Formula:
N(t) = N(0) * ( 1 + r)^t
where, N(0) is the number of bacteria present at the beginning of the experiment, r is the growth rate, t is the time taken/ elapsed.
Substituting the numbers for N(t), N(0) and t from the given description, we get the value of r.
220 = 20*(1+r)^(24 hours)
Solving for r, we get r = 0.105074.
1 week has (7 x 24 = 168) hours in it.
Therefore, N(168 hours) = 20*(1+0.105074)^168
Which is approximately 390 millions.
Hence there will be 390 millions bacteria at the end of 1 week.
Garbage is the most of the waste in the US.
There are 55%.
Weathering and erosion played a big role in forming the grand canyon. The rock was being weathered, most likely mechanical weathering, and then it eroded away. Think of a pebble that is in running water. When you pick it up, it is smooth, right. But before, it was pointy. So, the grand canyon was once a big rock, and weathering broke through it making it one of the wonders of the USA.