Acollection of coins contains 15 pennies, 12 dimes, and 7 quarters. what is the percentage of pennies in the collection?
express your answer to two significant figures and include the appropriate units.

Complete the sentence. the lower the hydrogen ion concentration, the the ph. higher lower closer to 7 closer to 0

Which of the following is not one of the steps in the scientific method a. hypothesize b. summarize c. analyze d. familiarize

Which of your 24 wells had indications that a chemical reaction occurred? how were you able to tell that a chemical reaction occurred? which of your 24 wells had indications that a physical reaction occurred? how were you able to tell that a physical reaction occurred? report on both mixing and evaporation. make a general statement about whether your hypotheses were validated or rejected. must your hypotheses be correct for this to be a successful laboratory?