Are there any rational numbers between 0.4 repeat and 4/9

Acylinder and its dimensions are shown. which equation can be used to find v, the volume of the cylinder in cubic centimeters?

David is spreading mulch on a triangular area of his flower bed. the coordinates of the vertices of the area are (1, 3), (9, 3), and (4, 6). what is the area of the triangle if each square has an area of 3 square feet?

Find the center and the radius of the circle with the equation: x^2-2x+y^2+4y+1=0?