Answer:
Quantity remaining= 27.5 grams
Step-by-step explanation:
If the initial quantity of the radioactive isotope= 220 grams
And for each half life it will reduce to half of its original quantity
For first half life
Quantity= 220/2
Quantity= 110 grams
Now for the second half life , the quantity to work with will be 110 grams
Second half life
Quantity= 110/2
Quantity= 55 grams
For the third half life , the quantity to work with is 55 grams
Third half life
Quantity= 55/2
Quantity= 27.5 grams
So after 3 half life's of this radioactive isotope, the amount remaining out of 220 = 27.5 grams.
Another simple way to do this
Since half life reduce the isotope by half of its original.
The third half life will reduce it by (1/2)^3= 1/8
So the quantity remaining= 1/8*220
Quantity remaining= 27.5 grams
Let's pick one person at random and call it the 'first'.
That person shakes hands with 29 other classmates.
Take another person different from the first, we'll call him the 'second'. Since he has already shaken hands with the first, he shakes hands with 28 other classmates.
The 'third' person will likewise shake hands with 27 other classmates, and so on.
Hence, the total number of handshakes is 29+28+27+...+2+1 = 29*30/2=435 handshakes
Answer:
The company must sell 60 or 70 items to obtain a weekly profit of 200.
Step-by-step explanation:
The profit is the difference between the revenue and the cost of a given task, therefore:
To have a profit of 200, we need to sell:
The company must sell 60 or 70 items to obtain a weekly profit of 200.
Answer:
The equation — E = mc2 — means "energy equals mass times the speed of light squared." It shows that energy (E) and mass (m) are interchangeable.
Hope this helped
Answer:
c
Step-by-step explanation:
