Answer:
The correct answers are:
1. They married royalty from other powerful lands
2. They threatened their rivals with war
Explanation:
In Northern Europe, like many parts of the world, marriages among different Kings and Empires was a common way to develop powerful alliances against a common foe.
More powerful than simple treaties, developing family relations would help to cement relationships and long-term stability of two empire.
However, in order to gain power, it was also common for Kings and Queens to threaten war. This was usually done to gain more land and increase power and taxation revenue.
The one that differentiates Christopher columbus from Bartolomeu Dias is : Columbus planned to reach Asia by sailing west across Atlantic Ocean, while Dias hope to reach Asia by sailing around Africa and through the Indian Ocean.
Hope this helps
You need more information. The correct tone would be formal though
