For Question 19, the passage from line 13-15 states that probability of rocks Earth to Mars > Mars to earth(since Mars has bigger orbit, it’ll catch more meteorites). Doesn’t it imply that the probability of rocks Mars to Earth < Earth to Mars. But the solution(D)s seem to contradict it. I’ve watched the walkthrough and know about the block-of-four. But I’m still not sold to it.
No, your interpretation is wrong ie., your text below is wrong
Lines 13-15 said probability of rocks from Earth2Mars=(1/10) probability of Mars2Earth, which means probailty of mars2Earth>Earth2Mars,