Answer:
true
Explanation:
Area = πr²
Differentiating in respect to r
we get,
dA/dr = 2πr
using chain rule,

since r = 4feet
so ,
2π(4) = 8π
Answer:
B
Explanation:
They are all one-dimensional
For the answer to the question above, I the answer is yes, It is <u><em>both </em></u><span><u><em>contaminated and </em></u><u><em>radioactive</em></u></span><u><em> at the same time</em></u>. That's why they keep the water spinning.I hope my answer helped you. Have a nice day!