If two charged objects, one with a charge of +4 µC and the other with a charge of +1 µC, are separated by a distance of 0.3 meters, what is the direction of the electric force acting on each charge according to Coulomb's Law?

Both charges are positive, so Coulomb’s Law says they repel each other. The force on the +4 µC charge pushes it directly away from the +1 µC charge, along the line that connects them. Likewise, the force on the +1 µC charge pushes it directly away from the +4 µC charge, along the same line. In short, each charge feels a force pointing outward along the line that joins the two charges. For example, if the charges are on a horizontal line, the +4 µC charge moves rightward while the +1 µC charge moves leftward.