What is the acceleration of a softball with a mass 0.5kg that is thrown with a force of 25 N?

In a laboratory, nakisha mixes sodium hydroxide solution with an indicator called phenolphthalein. when combined, they create a pink solution. nakisha wonders if mixing other solutions with phenolphthalein will also create this pink color. how could she use the scientific inquiry process to explore it further?

Idon’t quite understand this problem

When you push downward on a book at rest on a table, you feel an upward force. does this force depend on friction? defend your answer.