Why are sunspots dark? They are areas of solid material on the sun.
O They are old spots on the sun.
O They are cooler than the surrounding gases.
O They are warmer than the surrounding gases.

You are given an electron micrograph of a bacterial cell. in the micrograph you can clearly see three thin layers of different densities surrounding the cell. based on the micrograph, you can infer that this cell is and would appear after application of the gram stain procedure. gram-negative / pink gram-positive / purple gram-positive / pink gram-negative / purple