Answer:

Step-by-step explanation:
Let total number of students
Students went to the book fair:
Students went to book fair
Students who bought book:

Hence
of total students bought at least one book.
We are given our function as

For finding concavity , firstly we will find second derivative



now, we can find derivative again




now, we can know second derivative is undefined when denominator =0
so, we set denominator =0
and then we can solve for x


now, we can draw a number line and locate x=-4
and then we can find sign of second derivative on each intervals
so,
Concave downward interval:

When converted to a household measurement, 9 kilograms is approximately equal to a
Answer:
ok....let me try .....
<h2>..ok bro....sorry don't be angry
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