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
Answer:
53,901
Step-by-step explanation:
Here is the complete question :
In which number does the digit 5 have a value that is ten times greater than the value of the digit 5 in the number 245,093?
43,567
45,248
53,901
562,011
In the number 245,093 :
3 = units
9 = tens
0 = hundred
5 = thousand
4 = ten thousand
2 = hundred thousand
the value of 5 in the number is 5000. the number that would have a value that it 10 times greater than 5 in 245,093 must occupy the value of ten thousand.
looking through the options, it is only in 53,901 that 5 occupies a value of ten thousand
your first constant of propotionality is 10
The second constant of propotionality 5
Answer:
35 times StartFraction 5 Over 7 EndFraction
Step-by-step explanation:
Alejandro has gone to school (5/7) of the last 35 days.
We need to find the expression that can be used to determine the number of days Alejandro has gone to school.
So, the correct option is (b) "35 times StartFraction 5 Over 7 EndFraction".
A rate often involves time: e. g., 33 feet per second; also, we are finding the ratio of one type of measurement with respect to another: distance and time.
A proportion is often the ratio of different measures of the same thing:
e. g. 5 apples
------------
7 apples
