Answer:
The mean is the average you're used to, where you add up all the numbers and then divide by the number of numbers. The median is the middle value in the list of numbers. The mode is the value that occurs most often.
You can always make up numbers and try to draw it.
Let's say a = 1 for sake of simplicity.
If y=0 then x=0
<span>If y=1 then x=1
</span><span>If y=-1 then x=1
</span><span>If y=2 then x=4
</span><span>If y=-2 then x=4
</span>
As you can see, parabola opens to the right. Try drawing it to make sure you believe that.
Keep in mind, parabola only opens to the right if you are using the conventional x-y plane, where x-axis is horizontal and y-axis is vertical.
1.
Use the formula for the surface area of a sphere:
Plug in what we know:
Simplify the exponent:
Multiply:
This is an exact answer, if you want an approximate answer you can input 3.14 for pi:
2.
Use the formula for the volume of a sphere:
Plug in what we know:
Simplify the exponent:
Multiply:
This is an exact answer, if you want an approximate answer you can plug in 3.14 for pi:
3.
Since the two figures are similar, the ratio of their sides must be equal. So we can set up a proportion:
Cross multiply:
Divide 9 to both sides: