The purpose of Sparks' expedition into present-day Oklahoma and other southwestern land was to encourage positive relations with American Indians and to
A. establish borders between American and Spanish territories
B. search for gold and other precious metals
C. incite discord between American Indians and the Spanish living in the territory
D. trade fur with local American Indians and Spanish territorial residents

A. establish borders between American and Spanish territories

Explanation:

The Louisiana Purchase of 1803 gave the United States vast new lands that now meant that they shared a border with New Spain. President Thomas Jefferson in a bid to find out the extent of the land that was purchased, convinced Congress to fund an expedition to establish the boundaries of the new territory.

This expedition was the Sparks' Expedition also known as the Red River Expedition. They were led by Capt. Richard Sparks of the U.S. Army and their goal was to establish positive relations with American Indians in the new territories and to establish borders between American and Spanish territories.

The Spanish were not in support of the expedition however and sent a force to stop them. The Americans then headed back in order to avoid an international incident.  

angle a = 40.6°

step-by-step explanation:

for any right angle triangle we know the pythagoras theorem reveals

hypotenuse² = height²+base²

by this formula we will calculate the length of hypotenuse

h² = 6²+7²

⇒ h =√36+49 = √85 = 9.22

now from the given triangle sin a = height/ hypotenuse

                                                sin a = 6/9.22 = 0.651

therefore

so angle a = 40.6°

b. they tried to evict the squatters from the area.

so sorry if wrong