What is a pure substance? element, compound, mixture

It has been two weeks since charles met with daniel, a dietitian, who provided charles with a menu for weight loss. charles and his mother are going back to see daniel again with a chart of the food charles has eaten. the following lists what charles ate in one day: breakfast 1 banana, 1 cup of nonfat milk, 1 egg lunch 1 cup of carrots, 3 oz of steak, 1 apple, 1 cup of nonfat milk dinner 6 oz of skinless chicken, 1 baked potato, 3 oz of broccoli, 1 cup of nonfat milk

Write the chemical symbols for three different atoms or atomic cations with 27 electrons. asap!

Harvey kept a balloon with a volume of 348 milliliters at 25.0˚c inside a freezer for a night.  when he took it out, its new volume was 322 milliliters, but its pressure was the same.  if the final temperature of the balloon is the same as the freezer’s, what is the temperature of the freezer? the temperature of the freezer is  kelvins.