What do methanoic acid (hcooh), 1-chloroethane (ch2clch3), and propanone (ch3coch3) have in common? a. they are all carboxylic acids. b. they are in a homologous series. c. they have the same functional group. d. none of these

Functional groups are the set of atoms in a compound that's responsible for the chemical properties of the compound. 
the functional groups for the given compounds are as follows
methanoic acid = carboxylic group 
chloroethane = haloalkane
propanone = ketone
option A is incorrect as only one of the given compounds is a carboxylic acid, others have other functional groups
option C is incorrect as they have three different functional groups as stated above 
option B is incorrect as its not a homologous series. Homologous series are a set of compounds with same functional group that differs by a CH₂ group. since the functional groups are different it does not belong to a homologous series as well . 

correct option is D. none of these
as none of the other options are correct 

I’d have to say no because without oxygen in the water the fish would all be dead. so if you want to fish for dead fish, pick the ponds with the lowest oxygen concentrations.

If it releases 5 tons a day and there are 7 days a take that answer and multiply by 5 percent (0.05) to find the amount released in one week. leave a comment if you need more .