在ubuntu 12中安装乘客时出错

Question

我执行了以下命令来加载乘客模块：

sudo sh -c 'echo deb https://oss-binaries.phusionpassenger.com/apt/passenger jessie main > /etc/apt/sources.list.d/passenger.list'
sudo apt-get update
sudo apt-get upgrade
sudo apt-get install apache2 libapache2-mod-passenger

我遇到以下错误：

The following packages have unmet dependencies:
 libapache2-mod-passenger : Depends: libstdc++6 (>= 4.9) but 4.7.2-2ubuntu1 is to be installed
                            Depends: apache2-api-20120211 but it is not installable
                            Depends: passenger (= 1:5.0.26-1~jessie1) but it is not going to be installed

如何解决这些错误？