Yes but not directly.The text ads must be compatible with your content.You can change the ads colors and visitors think that the ads are contents.Because of that clicks may be increase. Sorry for my bad English
no, it doesn't. cost is cost regardless of font color. if you blend in your ads, it will increase your ctr but the cost will remain the same. or you actually mean CTR when you say cost?
Sultanofseo is correct, the cost is the same, however if you blend in the ads ands looks as if its your content, it'll increase your chance of people clicking on your ads.
yes google ask us to change our ads color to find the best color where match with our site color thus increase cost of click