Answer:
1) $283.50
2) 65.21 meters.
Step-by-step explanation:
Part 1)
We know that a spool of ribbon holds 6.75 meters.
A craft club buys 21 spools.
So, the total length of ribbon bought is:

Each meter costs $2. So, the total cost will be:

Part 2)
A spool holds 6.75 meters.
We bought 21 of them, so that total length we have is 141.75 meters.
The club used 76.54 meters.
So, the amount of ribbon that is left is represented by:

Subtract:

So, 65.21 meters of ribbon will be left.
Answer:
45 cm²
Step-by-step explanation:
Answer – C. the sample size 16 is too small
If we toss a coin 16 times in order to test the hypothesis
H0: p = 0.5 that the coin is balanced, we can't use the z-test for a proportion
in the situations because the sample size 16 is too small. The z-test is best
used when the sample size is greater than 30; when the sample size is less than
30, t-test is more appropriate.