The cylinder:
pi x r^2 x h
= pi x 8^2 x 20
then times it by a half
= 2009.6
The prism:
l x w
= 32 x 20
= 640
All up:
2009.6 +640
The shape equals 2649.6 cm sqaured
Answer:
It will give you the opposite sign.
Step-by-step explanation:
If you multiply two negatives you will end up with a positive and vice versa with positives. The same thing applies to dividing.
Easy
compare
y²=4px vs
y²=-4x
y²=y²
4px=-4x
divide both sides by x
4p=-4
divide both sides by 4
p=-1
p=-1
Answer:
15: A
16: C
Step-by-step explanation:
I have no idea but hopefully I helped you
Answer:
The half-life of the radioactive substance is of 3.25 days.
Step-by-step explanation:
The amount of radioactive substance is proportional to the number of counts per minute:
This means that the amount is given by the following differential equation:

In which k is the decay rate.
The solution is:

In which Q(0) is the initial amount:
8000 counts per minute on a Geiger counter at a certain time
This means that 
500 counts per minute 13 days later.
This means that
. We use this to find k.







So

Determine the half-life of the radioactive substance.
This is t for which Q(t) = 0.5Q(0). So







The half-life of the radioactive substance is of 3.25 days.