Which is an outer planet?

Is the alien theory a scientific claim? why or why not? just took the test it was , : " the alien theory is not a scientific claim because it is not based on valid data, there is no evidence to support it, and it does not come from a reliable source."

With i really need the correct answer!

Aperson gives a shopping cart an initial push along a horizontal floor to get it moving, and then lets go. the cart travels forward along the floor, gradually slowing as it moves. consider the horizontal force(s) on the cart while it is moving forward and slowing. which of the following statements is correct? (a) both a forward and a backward force are acting on the cart, but the forward force is larger. (b) only a forward force is acting which diminishes with time. (c) both a forward and a backward force are acting on the cart, but the backward force is larger. (d) only a backward force is acting, no forward force.