Answer:
7 days
Step-by-step explanation:
At 25% per day, it will take approximately 3 days to double the population, so approximately 6 days for the population to quadruple. Checking that number, we find it is not quite enough for the experiment, so another day is required.
"Guess and check" as a method of solution works especially well if you have an automated checker to evaluate your guess. A graphing calculator or spreadsheet can work well for this.
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We guess 3 days as the doubling time using the "rule of 72" that says the product of percentage and doubling time is about 72. That is, 72/25 ≈ 3. (This is only a very rough approximation of doubling time, best for rates near 8%.)
9. You need an exact answer. So I will give you it but I'll also give you an approximation because it might help you understand it more.
Because we know the cosine fo theta, we can evaluate the inverse cosine of -2/3 first to find theta.
= 131.81° approx.
Because 131.81° is in the second quadrant its third quadrant partner is 228.19°. Which would make the sine 0.75 approximately.
But we need an exact answer I suppose so which is this disgusting mess...
. I know it looks scary but it is basically all the steps we just did but without evaluating anything.
This can be simplified using: sin(x− y) = sinxcosy−cosxsiny
To... 
answer: 
10. Okay. So because we have a point we can say that...
θ = 
sin(θ) = +sin(
)
11. arcsin(-0.37) =
= -21.72°+2kπ or 201.72°+2kπ approx. where k has to be an integer
answer: idk if you want one or more solutions so I gave you them all.
12. arccos(-√3/2) = 
Remember that "k" must be an integer.
answer: 5π/6
Your answer would be 36,000 because he gets 3000 every month and every month for a year he would get your answer which would be 3000×12 which equals 36,000
Answer:
Human coastal development has also helped jellyfish thrive. The structures and construction that we have placed in the water, such as piers, marinas, oil platforms, artificial reefs, refuse, rubble, aquaculture pens and structures, etc. provide an abundance of habitats for polyps to settle on.