Answer:
Step-by-step explanation:
c !!
Answer: 30g
Step-by-step explanation:
In this question (t½) of isotope is 40 days, which means that after 40 days half of the sample would have decayed and half would be left as it is.
After 40 days ( first half life) 240 /2 = 120 g decays and 120 g remains left.
After another 40 days ( two half lives or 80 days) 120 /2 = 60 g decays and 60 g remains left .
after three half lives or 120 days, 60/2 = 30g decay and 30 g of the isotope will be left.
Answer:
13
Step-by-step explanation:
First, to find out how many book fit on one shelf, you will need to divide the total number of books by the toal number of shelves:
36 books / 3 shelves = 12 books/shelf
Because the question says that the bookstore order <em>another</em> 120 copies, this is means that the 120 books is in addition to the original 36 books.
Because we already know that the 36 books require 3 shelves, we still need to find how many shelves 120 books needs. So, we can divide books by number of how many books <em>can</em> fit on a shelf:
120 books / 12 books per shelf = 10 shelves
So to find the total number of shelves needed, add the number of shelves together:
3 + 10 = 13 shelves
Answer:
thanks for points
that's your only question?