The avian cardiovascular system is able to quickly respond to changes in levels of activity (e.g., resting vs. flying) via changes in heart rate, cardiac output, & blood flow (by vasocontriction and vasodilation of vessels).
A square is a quadrilateral with all right angles and all equal sides. A square is also a parallelogram, a rectangle, and a rhombus and has all the properties of all these special quadrilaterals. Figure 3 shows a square. Figure 3 A square has four right angles and four equal sides. Figure 4 summarizes the relationships of these quadrilaterals to one another.
A square is also a parallelogram whose sides intersect at 90Â° angles. Therefore, like a rectangle its opposite sides are congruent. However, a square has an added feature. It is also a rhombus. Therefore, all of its sides are congruent. A rectangle is a square when both pairs of opposite sides are the same length. This means that a square is a specialized case of the rectangle and is indeed a rectangle.