Your answer will be D. Hope I helped.
The four books had an average of 341 pages
Step-by-step explanation:
Given
Total number of books = 4
Pages in first book = x1 = 326
Pages in second book = x2 = 288
Pages in third book = x3 = 349
Pages in fourth book = 401
The average is given by:

The four books had an average of 341 pages
Keywords: Average, Division
Learn more about average at:
#LearnwithBrainly
Answer:
D) 5/8
Step-by-step explanation:
Since Susie has 5 books and 8 hair pins, you get 5:8 which can be transferred into a fraction of 5/8.
Answer:
Amount of Niobium-91 initially
= 300/91 =3.2967mol
2040 years = 3 ×680 = 3 half-lives
therefore, amount left = 0.4121mol
mass of Niobium-91 remaining = 0.4121 ×91 =37.5g
Please give brainliest