fail to 'gem install sqlite3' - ruby-on-rails

Question

When I run rails new todo, it appears as follows(related question Make sure that 'gem install ~ ' succeeds before bundling).
Gem::RemoteFetcher::FetchError: SSL_connect returned=1 errno=0 state=SSLv3 read
server certificate B: certificate verify failed (https://rubygems.org/gems/sqlit
e3-1.3.10-x64-mingw32.gem)
An error occurred while installing sqlite3 (1.3.10), and Bundler cannot
continue.
Make sure that `gem install sqlite3 -v '1.3.10'` succeeds before bundling.
When I run gem install sqlite3, it appears as follows.
C:\Ruby21-x64>gem install sqlite3
Temporarily enhancing PATH to include DevKit...
Building native extensions. This could take a while...
ERROR: Error installing sqlite3:
ERROR: Failed to build gem native extension.
C:/Ruby21-x64/bin/ruby.exe extconf.rb
checking for sqlite3.h... no
sqlite3.h is missing. Install SQLite3 from http://www.sqlite.org/ first.
*** 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=C:/Ruby21-x64/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
extconf failed, exit code 1
Gem files will remain installed in C:/Ruby21-x64/lib/ruby/gems/2.1.0/gems/sqlite
3-1.3.10 for inspection.
Results logged to C:/Ruby21-x64/lib/ruby/gems/2.1.0/extensions/x64-mingw32/2.1.0
/sqlite3-1.3.10/gem_make.out
Following my textbook, I have already downloaded 'sqlite-shell-win32-x86' , made 'c:\sqlite3' folder , added 'sqlite3.exe' in that folder and added path 'c:\sqlite3'.
What should I do? I can't start RoR...
Added
He says
checking for sqlite3.h... no
sqlite3.h is missing.
I found sqlite3.h(this is in the sqlite-amalgamation folder), so I guess what I do next is to put it in the proper folder. Where is that?
I put sqlite3.h in the folder in which ruby.exe is, but he still says sqlite3.h is missing..

Answer 1

You lack the system dependecies that the gem requires.
sudo apt-get install sqlite3 libsqlite3-dev
http://www.askyb.com/sqlite/installing-sqlite-in-ubuntu/