Finding the voltage and current across a DC diode
Figure out if the diode is on or off.
(Hint what would the voltage at the diode be if the diode were not there.)
Once you know that, you should know what \$V_D\$ is. 
Knowing \$V_D\$ you can calculate \$I_{R1}\$ and \$I_{R2}\$.
\$I_D\$ = The difference between \$I_{R1}\$ and \$I_{R2}\$.