how to install failed packages on RHEL5.5?

Hi,

Am new to linux. I have installed RHEL5.5 using dell utility and RHEL5.5 installation CD's.

After installation updated and tried to install " R " software. While installaing many packages not installed like gcc, c, etc. Kinldy look it screenshot. Could anyone help me to solve this problem? Thanks in advance..

Regards,

Sathish