Melody

I just did this question.

Re: 9-5(-3z+8k) use k= -2 and z= 6

$$9-5(-3*6+8*-2)\\\\
=9-5(-18-16)\\\\
=9-5(-34)\\\\
=9+5*34\\\\
=9+170\\\\
=179$$

Technically anonymous is right.

There are 1024MB in 1GB

This is because with data storage everything is in powers of 2

2^10=1024

It is just rounded to 1000 as an estimate because 1000 is easy to work with.

If I've said anything wrong here feel free to correct me.

look at poor CPhill. The sun is blinding him because his specs got stolen!    Whoever could be so mean!  ♬     

I like answering questions

and i like to learn from how other people answer questions (When I already know the answer but I am learning a new way to teach it)

and, when there is time I really like learning new things from difficult questions that I cannot already do!

I like puzzles but there is hardly ever enough time for me to enjoy them.  

I really liked this question Rose.

I'd do it CPhill's way.

the whole circumference it 2pi*r

But you only have 80degrees out of a total of 360 degrees in the whole cirlce.

so the answer must be given by

$$arc\;length= \frac{80}{360}\times 2\pi r => \frac{80}{360}\times 2\pi\times 18$$    etc

I am glad that you worked it out DragonSlayer.  

If you had given data someone would have answered but your question was a bit vague.

It is always good when you work out your own problems anyway.  It gives a you an added sense of achievement. 

how did you cross out those numbers Ninja?

$$(x-1)(2x^3+2x^2+2)\\\\
=x(2x^3+2x^2+2)-1(2x^3+2x^2+2)\\\\
=2x^4+2x^3+2x-2x^3-2x^2-2\\\\
=2x^4-2x^2+2x-2$$

Good work DragonSlayer