title: Is it impossible to install R 4.0 on Ubuntu 18.04.4 LTS because r-base-core requires a libc6 version >= 2.29?
body: <p>I am trying to install R 4.0 on Ubuntu 18.04.4 LTS but I keep getting errors of </p>
  
  <pre><code>&gt; sudo apt install r-base-core
  Reading package lists... Done
  Building dependency tree
  Reading state information... Done
  Some packages could not be installed. This may mean that you have
  requested an impossible situation or if you are using the unstable
  distribution that some required packages have not yet been created
  or been moved out of Incoming.
  The following information may help to resolve the situation:
  
  The following packages have unmet dependencies:
   r-base-core : Depends: libc6 (&gt;= 2.29) but 2.27-3ubuntu1 is to be installed
                 Depends: libicu66 (&gt;= 66.1-1~) but it is not installable
                 Depends: libreadline8 (&gt;= 6.0) but it is not installable
                 Recommends: r-recommended but it is not going to be installed
                 Recommends: r-base-dev but it is not going to be installed
                 Recommends: r-doc-html but it is not going to be installed
  E: Unable to correct problems, you have held broken packages.
  </code></pre>
  
  <p>when trying to install. I have removed and deleted R 3.6.3 and have added </p>
  
  <pre><code>deb https://cloud.r-project.org/bin/linux/ubuntu bionic-cran40/
  </code></pre>
  
  <p>in my <code>/etc/apt/sources.list</code> file. Note that the above requires <code>libc6 (&gt;= 2.29)</code> yet from what I have seen, it is NOT AVAILABLE for 18.04. Does this mean I have to upgrade to 19.04, or 20.04 in order to run R 4.0?</p>