The "Git Bash" terminal will put the root of each drive in /<drive-letter>, so drive C:\ will be at /c/, drive E:\ will be at /e/, etc. Try cd /c/myapp/abc.
/<drive-letter>
C:\
/c/
E:\
/e/
cd /c/myapp/abc
that should be /mnt/drive-letter in your "Git Bash" terminal