Which statement is true about this fuel cell? It is self contained like a battery.
It continually needs to be charged.
It has an electrolyte that acts as a salt bridge.
It does not require the input of fuels from an outside source.

r just means there's a number of carbon in teh chain. for example rcooh means that after x number of carbon, the chain ends with cooh.

explanation:

the answer is 1260

you spend 7 hours in school for 1 school day with 5 school days in 1 school week with 36 school weeks in a school year.

7*5*36= 1260 it's all about multiplying