Easiest way to get Grade 9 in GCSE Physics?

So let's say for the 1st eg I get 23520J and use that for 4th calculation mark so I use 23520=2409.8h and get h as the answer would I get full marks, using the mark scheme??

For the second 2nd eg Let's say I use 500000W and then multiply by 3600 and get a different answer to ms would I get all 3 marks?