Can u with tee rock part and plz asap i really need

Half-life = time in which half of material is lost

1/4 = 1/2 x 1/2 so 2 half lives have gone by if only 1/4 of it is left.

age of rock = 2 x half life = 2x1.3 = 2.6 billion years.

Here, Left amount of Uranium = 1/4

So, Number of Half lives gone by = 1/2 / 1/4 = 2

Life after 1 half-life = 1.3 billion years
So, With 2 half-lives, it would be: 1.3 * 2 = 2.6 billion years

In short, The Rock is 2.6 billion Years Old

For second question, "sea floor spreading and plate tectonics indicate that the continents do move or shift" and it is the basic principle of Continental drift theory.

Hope this helps!