1. Answer: components
A two dimensional vector can be divided into two parts called horizontal component and vertical component.
A three dimensional vector can be divided into three components: one along x-axis, one along y-axis and one along z-axis.
Hence, the vector parts that add up to the resultant are called components.
2. Answer: 5 miles.
The resultant distance along the straight line from the starting point to the end point would be the displacement.
The displacement would be equal to the magnitude of the hypotenuse formed in the right triangle.
Displacement,
3. Answer: Scalar
A scalar quantity has only magnitude. For example, speed and distance are scalar quantities and can be normally added to find the total.
A vector quantity has both magnitude as well as direction. The components are summed according to vector addition rules. For example, velocity, acceleration, force etc.