I've made sure that all the files are in the root of the repository as recommended in this discussion. However, as I follow the instructions in this section of the book, I can't get through the section without the problems. What do you think is happening with my system that's causing the error? I have no clue at the moment of what the problem means despite reading the following in the log. Thanks in advance for your help!

stanley@ubuntu:~/rails_sample/first_app$ git push heroku master
Warning: Permanently added the RSA host key for IP address '50.19.85.156' to the list of known hosts.
Counting objects: 96, done.
Compressing objects: 100% (79/79), done.
Writing objects: 100% (96/96), 28.81 KiB, done.
Total 96 (delta 22), reused 0 (delta 0)

-----> Heroku receiving push
-----> Ruby/Rails app detected
-----> Installing dependencies using Bundler version 1.2.0.pre
       Running: bundle install --without development:test --path vendor/bundle --binstubs bin/ --deployment
       Fetching gem metadata from https://rubygems.org/.......
       Installing rake (0.9.2.2)
       Installing i18n (0.6.0)
       Installing multi_json (1.3.5)
       Installing activesupport (3.2.3)
       Installing builder (3.0.0)
       Installing activemodel (3.2.3)
       Installing erubis (2.7.0)
       Installing journey (1.0.3)
       Installing rack (1.4.1)
       Installing rack-cache (1.2)
       Installing rack-test (0.6.1)
       Installing hike (1.2.1)
       Installing tilt (1.3.3)
       Installing sprockets (2.1.3)
       Installing actionpack (3.2.3)
       Installing mime-types (1.18)
       Installing polyglot (0.3.3)
       Installing treetop (1.4.10)
       Installing mail (2.4.4)
       Installing actionmailer (3.2.3)
       Installing arel (3.0.2)
       Installing tzinfo (0.3.33)
       Installing activerecord (3.2.3)
       Installing activeresource (3.2.3)
       Installing coffee-script-source (1.3.3)
       Installing execjs (1.3.2)
       Installing coffee-script (2.2.0)
       Installing rack-ssl (1.3.2)
       Installing json (1.7.3) with native extensions
       Installing rdoc (3.12)
       Installing thor (0.14.6)
       Installing railties (3.2.3)
       Installing coffee-rails (3.2.2)
       Installing jquery-rails (2.0.2)
       Using bundler (1.2.0.pre)
       Installing rails (3.2.3)
       Installing sass (3.1.18)
       Installing sass-rails (3.2.5)
       Installing sqlite3 (1.3.6) with native extensions
       Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension.
       /usr/local/bin/ruby extconf.rb
       checking for sqlite3.h... no
       sqlite3.h is missing. Try 'port install sqlite3 +universal'
       or 'yum install sqlite-devel' and check your shared library search path (the
       location where your sqlite3 shared library is located).
       *** extconf.rb failed ***
       Could not create Makefile due to some reason, probably lack of
       necessary libraries and/or headers.  Check the mkmf.log file for more
       details.  You may need configuration options.
       Provided configuration options:
       --with-opt-dir
       --without-opt-dir
       --with-opt-include
       --without-opt-include=${opt-dir}/include
       --with-opt-lib
       --without-opt-lib=${opt-dir}/lib
       --with-make-prog
       --without-make-prog
       --srcdir=.
       --curdir
       --ruby=/usr/local/bin/ruby
       --with-sqlite3-dir
       --without-sqlite3-dir
       --with-sqlite3-include
       --without-sqlite3-include=${sqlite3-dir}/include
       --with-sqlite3-lib
       --without-sqlite3-lib=${sqlite3-dir}/lib
       --enable-local
       --disable-local
       Gem files will remain installed in /tmp/build_3tplrxvj7qa81/vendor/bundle/ruby/1.9.1/gems/sqlite3-1.3.6 for inspection.
       Results logged to /tmp/build_3tplrxvj7qa81/vendor/bundle/ruby/1.9.1/gems/sqlite3-1.3.6/ext/sqlite3/gem_make.out
       An error occurred while installing sqlite3 (1.3.6), and Bundler cannot continue.
       Make sure that `gem install sqlite3 -v '1.3.6'` succeeds before bundling.
 !
 !     Failed to install gems via Bundler.
 !
 !     Heroku push rejected, failed to compile Ruby/rails app

To [email protected]:growing-mountain-2788.git
 ! [remote rejected] master -> master (pre-receive hook declined)
error: failed to push some refs to '[email protected]:growing-mountain-2788.git'

------Gemfile------------------------

As requested, here's the auto-generated gemfile:

source 'https://rubygems.org'

gem 'rails', '3.2.3'

# Bundle edge Rails instead:
# gem 'rails', :git => 'git://github.com/rails/rails.git'

gem 'sqlite3'

gem 'json'

# Gems used only for assets and not required
# in production environments by default.
group :assets do
  gem 'sass-rails',   '~> 3.2.3'
  gem 'coffee-rails', '~> 3.2.1'

  # See https://github.com/sstephenson/execjs#readme for more supported runtimes
  # gem 'therubyracer', :platform => :ruby

  gem 'uglifier', '>= 1.0.3'
end

gem 'jquery-rails'

# To use ActiveModel has_secure_password
# gem 'bcrypt-ruby', '~> 3.0.0'

# To use Jbuilder templates for JSON
# gem 'jbuilder'

# Use unicorn as the app server
# gem 'unicorn'

# Deploy with Capistrano
# gem 'capistrano'

# To use debugger
# gem 'ruby-debug'