Can someone please help for question 1? this is really important!!

Maria wants to determine which type of disinfectant kills the most bacteria. which of the following is the best way for maria to determine this? a. ask ten different companies that make disinfectants which type is best. b. put the same amount and species of bacteria on ten identical plates, and add ten different kinds of disinfectant to each plate. c. interview ten different people to determine which type of disinfectant they prefer. d. put the same amount and species of bacteria on ten identical plates, and add a different disinfectant to each plate.

Use the periodic table to determine how many grams of oxygen would be required to react completely with 859.0 g c2h2

How does electronegativity changes as we move from left to right across a period