Answer:
4.62 hrs
Step-by-step explanation: there is 1g of pb-209 present and it's half life (time to reduce to it's half value) is 3.3 hours.
Half of the original value = 1g/2
= 0.5g
So
0.5g = 3.3 hrs
Now 70% of 1g is 0.7g
Value of pb-209 remaining at 70% removed is 1-0.7=0.3g
So the Time to decay to 0.3g is
=(0.7*3.3)/0.5
=2.31/0.5
= 4.62 hrs
Answer:
1/3
Step-by-step explanation:
2+2+2=6
There are three 3's
Answer:
1st option
Step-by-step explanation:
Given the zero product
(x - 3)(x + 5) = 0 , then
x - 3 = 0 ; x + 5 = 0
The problem is, I don't think that you estimated for letter a, so you can't do letter b.
The frequency table is attached.
Since there were 30 people out of the 60 that received cold medicine, that means that 60-30=30 people did not.
Since 26 people had a cold longer than 7 days, this means 60-26=34 had a cold that was less than or equal to 7 days.
14 people had a cold longer than 7 days and received medicine; this means that 26-14=12 people had a cold longer than 7 days and did not receive medicine.
30-14=16 people received medicine and had a cold less than or equal to 7 days.
30-12=18 people did not receive medicine and had a cold less than or equal to 7 days.