2. the water quality is "good" if the count of e coli is 0; otherwise, the water quality is still bad. calculate the proportion of wells with "good" water to wells whose water is not good. from this measure does it appear that the quality of water improved? explain and use the proportions that you calculated. (in g11 and h11 calculate the percent clean for before and after.)

Modern pennies are composed of zinc coated with copper. a student determines the mass of a penny to be 2.482 g and then makes several scratches in the copper coaling (to expose the underlying zinc). the student puts the scratched penny in hydrochloric acid, where the following reaction occurs between the zinc and the hcl (the copper remains undissolved): zn(s) + 2 hcl(aq) → h2(g) + zncl(aq)the student collects the hydrogen produced over water at 25 °c. the collected gas occupies a volume of 0.899 l at a total pressure of 79 j mmhg. calculate the percent zinc (by mass) in the penny. (assume that all the zn in the penny dissolves.)

The missing component to the table to the right or indicated with orange letters complete the table by filling in the corresponding numbers or symbols

Using the first volume and temperature reading on the table as v1 and t1, solve for the unknown values in the table below. remember to use the rules of significant figures when entering your numeric response.