360 tiles because you have to multiply 12x30.
PEMDAS. parenthesis, exponents, multiple or divide (whichever come first from left to right), add or subtract (whichever comes first from left to right)
So first do stuff in parenthesis.
Then do divide because thats next on the list and it happens earlier than the multiply one.
So, A
Answer:
see explanation
Step-by-step explanation:
The diagonals of a parallelogram bisect each other , then
CO = OA = b
DO = OB = a
(a)
CA = CO + OA = b + b = 2b
(b)
DC = DO + OC = a - b
(c)
CB = CO + OB = b + a = a + b
To calculate the remaining caffeine, we use the radioactive decay formula which is expressed as An = Aoe^-kt where An is the amount left after t time, Ao is the initial amount and k is a constant we can calculate from the half-life information. We do as follows:
at half-life,
ln 1/2 = -k(6)
k = 0.12/hr
An = 80e^-0.12(14)
An = 15.87 mg