Which is a true statement about tobacco and smoking? a. tobacco ads can be within 1000 feet of schools and playgrounds. b. no more than 5 million americans use smokeless tobacco. c. every day almost 5,000 american young people smoke their first cigarette. d. of all teens who smoke a first cigarette, only 10% will become regular smokers.

Dumbledore decides to gives a surprise demonstration. he starts with a hydrate of na2co3 which has a mass of 4.31 g before heating. after he heats it he finds the mass of the anhydrous compound is found to be 3.22 g. he asks everyone in class to determine the integer x in the hydrate: na2co3·xh2o; you should do this also. round your answer to the nearest integ