[R] breaks/bins question

Thank you Joshua and Jim--I got the tick marks on finally! One last question: I am supposed to make bins in 1, 2 and 5 mm increments for fish up to 170 mm. I assume these are the breaks? So breaks = 170 for 1 mm and 340 for 2 mm and 1550 for 5 mm? I couldn't find any specific examples in the

[R] need tick marks by 10s or 20s up to 200 on x axis

I haven't been able to get any code to make more tick marks than the default by 50. Thanks! Code: hist(OMY$FL, main = "2010 Oncorhynchus mykiss Fork Length Frequencies at Buck Creek Reach 1", include.lowest = TRUE, col = "blue", border = "white", breaks = 140,xlab = "Fork Length in mm", ylab