I think external forces acting on an object may include friction, gravity, normal force, drag, tension, or a human force due to pushing or pulling can be represented by a free body diagram.
Answer:
An F1 offspring could produce four types of gametes, RY, Ry, rY, and ry. The F2 generation supports the independent-assortment model and refutes the linkage model.
Explanation:
Awnser: independent variable or control
Explanation: