Answer:
See Below
Step-by-step explanation:
The surface area of cylinder is given by the formula:

Where
r is radius ( diameter is 4, so radius is 4/2 = 2)
h is height ( h = 9)
Lets find original surface are:

<u>Halving diameter:</u>
diameter would be 4/2 = 2, so radius would be 2/2 = 1
So, SA would be:

<u>Halving height:</u>
Height is 9, halving would make it 9/2 = 4.5
Now, calculating new SA:

Original SA is
,
Halving diameter makes it 
Halving height makes it 
So, halving diameter does not have same effect as halving height.
Answer:
Step-by-step explanation:
10a-15b
Answer:
1.2192 hectares
Step-by-step explanation:
1 foot² = .3048 meter²
40000 feet² * .3048 = 12192 meters²
12192/10000 = 1.2192
Answer:
10 times
Step-by-step explanation:
there are a total of 200 coins
each time he makes a selection the probability of selecting a dime is 40/200 or 1/5
if he makes 50 selections, the probability is 1/5(50) which is 10 times