Answer:
About 0.559 seconds
Step-by-step explanation:
The height equation is:

Where
is the initial height of the book, which is 5, so we can write:

Now, we want time it took for the book to reach ground (h = 0)
So, we substitute h = 0 and solve for t:

It took about 0.559 seconds for the book to reach the ground
Answer: 47/8
Step-by-step explanation: To write a mixed number as an improper fraction, first multiply the denominator by the whole number and then add the numerator. Finally, we will put our new number over our old denominator and we have our answer which is 47/8.
Therefore,
can be rewritten as the improper fraction 47/8.
Big/small=4/7
r1/r2=4/7 where r1, r2 are radius of a big and small circles respectively
r1/3=4/7
r1=12/7
circumference of a big circle is2πr1=2π*12/7=24π/7 cm