2). For this problem you have to prime factorize the numbers so……620 so the answer would be 2*2*5*5*7. Now do the same thing for 260 so the answer is 2*2*5*13

620 260

/ \ / \

2 310 2 130

/ \ / \

2 155 2 65

/ \ / \

5 35 5 13

/ \

7 5

As for the last one I can’t answer.