<span>c)1 + 2cot^2x + 2cscx cotx
because cosc^2x=1+cot^2x</span>
The answer should be 0.0004702
Answer:
I am trying to do the same it's so HARD
If
is the amount of strontium-90 present in the area in year
, and it decays at a rate of 2.5% per year, then

Let
be the starting amount immediately after the nuclear reactor explodes. Then

or simply

So that after 50 years, the amount of strontium-90 that remains is approximately

or about 28% of the original amount.
We can confirm this another way; recall the exponential decay formula,

where
is measured in years. We're told that 2.5% of the starting amount
decays after 1 year, so that

Then after 50 years, we have
