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
1 mile = 5,280 feet
Car + space = 13.5 + 3 = 16.5 feet
5,280 / 16.5 = 320
Answer: 320 cars
Answer:
35
Step-by-step explanation:
6x-4x= 2x
+63+7=70
70/2=35
What is the mean,mode,range <br><br>
6,13,8,9,10,18,10,15,19
lesya [120]
Answer:
Mode-10
Mean-12
Range-13
Step-by-step explanation:
Mode is the most common which is 10
Mean is the averge so you add them all together then diviede based on how many numbers there are
Range is the difference between the smallest and biggest number so you just subtract. Biggest- smallest
Answer:
I did for you but I don't know you will understand my HANDWRITING or not .
:(