Answer:
Part a) The volume of the air is 
Part b) The volume of the plastic is 
Step-by-step explanation:
we know that
The volume of the sphere is equal to

step 1
Find the volume of the complete ball (air +plastic)
we have
------> the radius is half the diameter
substitute


step 2
Find the volume of the air
we have that
The plastic is 2 mm thick
Convert to cm
2 mm=2/10=0.2 cm
so
The radius of the interior of the ball is

substitute

-----> this is the volume of the air (interior of the ball)
step 3
Find the volume of the plastic
we know that
The volume of the plastic is equal to the volume of the complete ball minus the volume of the air
so

I’m pretty sure the answer is 9 to 1
The perimeter:
40+35+16+16+125.7= 232.7 m
btw lowkey frustrating that they alternate between cm and m
Answer:
If the null hypothesis is true in a chi-square test, discrepancies between observed and expected frequencies will tend to be small enough to qualify as a common outcome.
Step-by-step explanation:
Here in this question, we want to state what will happen if the null hypothesis is true in a chi-square test.
If the null hypothesis is true in a chi-square test, discrepancies between observed and expected frequencies will tend to be small enough to qualify as a common outcome.
This is because at a higher level of discrepancies, there will be a strong evidence against the null. This means that it will be rare to find discrepancies if null was true.
In the question however, since the null is true, the discrepancies we will be expecting will thus be small and common.