True or false : ) 1 . other than the use of special instructions the chromosphere is only visible during a solar eclipse when the photosphere is blocked . 2 . as a star ages it's internal composition changes as nuclear reactions in the star's core convert one element into another 3 . astronomers can sometimes identify binary star's even if only one star is visible 4 . using the parallax technique , astronomers can accurately measure the distance of star's up to 300 pc away 5 . stars are assigned a spectral type , with m being the hottest stars .