Standing waves of frequency 68 hz are produced on a string that has mass per unit length 0.0160 kg/m. with what tension must the string be stretched between two supports if adjacent nodes in the standing wave are to be 0.74 meters apart?

It's because 3 if it was 10 it wouldn't look right do it goes up to 4d

The answer is frictional force

Honestly "global warming" may be a slight possiblity, however they called it "climate change" because its not real, in fact we had one of our coldest days here not too long ago, and the "issues" with this subject is a blindfold for actual problems.