R version 3.2.2 (2015-08-14) -- "Fire Safety"
Copyright (C) 2015 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)

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> x <- c(4.99,29.99,1.99,9.99,199.9,299.9,19.99,2.99,1.99,0.99,9.99,39.99,49.99,29.99,9.99,29.99,9.99,9.99,4.99,39.99,5.99,9.99,74.99,39.99,1.99)
> par4 = 'Unknown'
> par3 = 'FALSE'
> par2 = 'blue'
> par1 = ''
> xlab = 'Price'
> main = 'App Store's Top 25 Paid Apps Price'
Error: unexpected symbol in "main = 'App Store's"
Execution halted