Answer:
Given that,
The number of grams A of a certain radioactive substance present at time, in years
from the present, t is given by the formula

a) To find the initial amount of this substance
At t=0, we get


We know that e^0=1 ( anything to the power zero is 1)
we get,

The initial amount of the substance is 45 grams
b)To find thehalf-life of this substance
To find t when the substance becames half the amount.
A=45/2
Substitute this we get,


Taking natural logarithm on both sides we get,







Half-life of this substance is 154.02
c) To find the amount of substance will be present around in 2500 years
Put t=2500
we get,




The amount of substance will be present around in 2500 years is 0.000585 grams
We want to multiply the monomial
by the monomial
.
Remember that to multiply monomials we need to use the laws of exponents; in this case, the law for multiplying powers with the same base. The rule says that, when you multiply powers of the same base, you just need to add the exponents:
,
. Also, is worth pointing out that the exponent of a variable with no exponent is 1:
.
Remember that we also need to multiply their coefficients , which are the numbers that multiply the variables; again, variables with no numbers have a coefficient of 1, so
. Multiply coefficients is easy, you just need to multiply them as you usually do with everyday numbers.
Let's apply all of that to our multiplication:

We can conclude that 2x times x squared is 2x cubed.
Answer:
$110
Step-by-step explanation:
So first you have to do 15*4. We get the 4 from the admission fees and the 15 from the number of dances they attend. From this answer we can see the total of money they will be paying for admission for the 15 dances.
15*4=$60
However, our answer isn't just $50 as we are also told membership costs $50. So no we add $50 to $60, which gives us an answer of $110, which is the amount the member will pay if they attend 15 dances during the school year.
X-10>15.........................................