新しいRailsアプリケーションを作成しました。サーバーを起動しようとすると、次のエラーが発生します。
[bathakarai@Project1-CO samp]$ rails server
/home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/railties-3.2.13/lib/rails/script_rails_loader.rb:11: warning: Insecure world writable dir /usr in PATH, mode 040777
/home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/bundler-1.3.4/lib/bundler/runtime.rb:216: warning: Insecure world writable dir /usr in PATH, mode 040777
/home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/execjs-1.4.0/lib/execjs/runtimes.rb:51:in `autodetect': Could not find a JavaScript runtime. See https://github.com/sstephenson/execjs for a list of available runtimes. (ExecJS::RuntimeUnavailable)
from /home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/execjs-1.4.0/lib/execjs.rb:5:in `<module:ExecJS>'
from /home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/execjs-1.4.0/lib/execjs.rb:4:in `<top (required)>'
from /home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/coffee-script-2.2.0/lib/coffee_script.rb:1:in `require'
from /home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/coffee-script-2.2.0/lib/coffee_script.rb:1:in `<top (required)>'
from /home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/coffee-script-2.2.0/lib/coffee-script.rb:1:in `require'
from /home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/coffee-script-2.2.0/lib/coffee-script.rb:1:in `<top (required)>'
from /home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/coffee-rails-3.2.2/lib/coffee-rails.rb:1:in `require'
from /home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/coffee-rails-3.2.2/lib/coffee-rails.rb:1:in `<top (required)>'
from /home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/bundler-1.3.4/lib/bundler/runtime.rb:72:in `require'
from /home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/bundler-1.3.4/lib/bundler/runtime.rb:72:in `block (2 levels) in require'
from /home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/bundler-1.3.4/lib/bundler/runtime.rb:70:in `each'
from /home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/bundler-1.3.4/lib/bundler/runtime.rb:70:in `block in require'
from /home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/bundler-1.3.4/lib/bundler/runtime.rb:59:in `each'
from /home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/bundler-1.3.4/lib/bundler/runtime.rb:59:in `require'
from /home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/bundler-1.3.4/lib/bundler.rb:132:in `require'
from /home/bathakarai/gold/Ruby/Practice/Rails/samp/config/application.rb:7:in `<top (required)>'
from /home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/railties-3.2.13/lib/rails/commands.rb:53:in `require'
from /home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/railties-3.2.13/lib/rails/commands.rb:53:in `block in <top (required)>'
from /home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/railties-3.2.13/lib/rails/commands.rb:50:in `tap'
from /home/bathakarai/.rvm/gems/ruby-2.0.0-p0/gems/railties-3.2.13/lib/rails/commands.rb:50:in `<top (required)>'
from script/rails:6:in `require'
from script/rails:6:in `<main>'
このエラーを修正するにはどうすればよいですか?