I'm in middle school too and I could help u but I have absolutely no idea what you are asking.
Answer:
age = 63.2 years
Explanation:
Given data
Number of years = 31
number of seconds = 1 billion
Age = ?
Solution
First we convert seconds to minutes
minutes = 1000000000 / 60
minutes = 16666666.667
Now convert minutes to hours
hours = 16666666.667 / 60
hours = 277777.778
Now convert hours to days
days = 277777.778 / 24
days = 11574.074
Now convert days to months
months = 11574.074 / 30
months = 385.802
Now convert months to years
years = 385.803 / 12
years = 32.15
Now add these years with given years
age = 31 + 32.15
age = 63.2 years
4.8 g/cm3 with sig figs since it's mass/volume you divide 76 grams by 16 cm3
Forests and prairies are examples of ecosystems on land. An ecosystem is a community of living things. Members survive by interacting with each other and with their environment. At first glance, the ocean seems like one big ecosystem.
From the equation of the reaction; for every 1 mole of copper, the reaction uses 2 moles of silver nitrate.
<h3>What is a reaction?</h3>
A chemical reaction involves the transformation of one chemical specie into another. The reaction is not shown here hence the question is incomplete.
However, the reaction should be of the sort; Cu + 2AgNO3 ---> Cu(NO3)2 + Cu. Thus, for every 1 mole of copper, the reaction uses 2 moles of silver nitrate.
Learn more about chemical reaction: brainly.com/question/6876669