kiem tra 3

https://drive.google.com/open?id=0B4K8lkHvBK58WVFHbEV6TWd0T2s
https://drive.google.com/open?id=0B4K8lkHvBK58OXctdVBhSVRFUG8

Excel
bai tap 11.3
bai tap 11.4