In February 2014, Facebook announced its acquisition of Whatsapp, a widely-used messaging application. The deal was valued at an approximate sum of 19 billion US Dollars. This purchase was one of the largest acquisitions in the tech industry at the time. Facebook's decision to acquire Whatsapp aligned with its strategy to expand its presence in the mobile messaging market and to grow its user base. The substantial investment reflects the high value placed on Whatsapp's significant global user network and rapid growth rate in the sector. The correct answer is 19 billion US Dollars.
Match the following airlines with the countries where they are headquartered.
| Airlines | Countries |
|---|---|
| 1. AirAsia | A. Singapore |
| 2. AZAL | B. South Korea |
| 3. Jeju Air | C. Azerbaijan |
| 4. Indigo | D. India |
| 5. Tigerair | E. Malaysia |