Since overnutrition is a bigger problem in America than malnutrition, there's probably little you can do about your diet to increase your height. As for exercise, that makes little difference. Your best bet is probably to get as much sleep as you can, since you do all your growing at night.
<< contrary to what many believe, genetics only play about 25% of your height. Other 75% has to do with nutrients, exercise, sleeping well (not staying up late, going to bed between 9-10:30). >>
This is not really something you can quantify. Perhaps if you live in Ethiopia, you are correct, in that getting proper nutrition there may be the exception to the rule if there is a famine and malnutrition is widespread. Almost everyone here in the U.S., however, gets their basic requirements for calcium, protein, and calories. And if vitamins are a problem, that can easily be met with supplements. Genetics is the main determinant for what your height will be.