Simplify this expression 2a-1+8b-12b+7a-12

Can someone answer it, and plot it, for 20 points and brainliest answer? p. s. they're the same ! : )

The volume of a sphere is increased by 6%. calculate the corresponding percentage increased in it area.

Sandy is upgrading her internet service. fast internet charges $20 for installation and $52.45 per month. quick internet has free installation but charges $57.45 per month. part 1 out of 2 complete the equation that can be used to find the number of months after which the internet service would cost the same. use the variable x to represent the number of months of internet service purchased.