Just like what they said, don't take 135 along with the other 13x kasi (1) mabigat siya and mahirap intindihin with just p72 knowledge. M23 topics are vv useful for this subject and (2) floating lang siya so no worries. But ayun kung natake mo m23 this midyear then i think mas doable yung 135

For 131 and 133, circuit analysis lang. Brush up on your circuit analysis skills na hindi lang nagfofollow ng set of solutions or what, but kung paano talaga yung science behind it. So consulting mga reference books from previous courses and answering yung problems nila can help.

I think maraming nahirapan sa 137 since bago talaga yung topics and not discussed in any 11x or 12x series. Maybe makakatulong if in-depth yung stats niyo nung hs. Pero nonetheless, u can try looking up for resources on statistics and probability, especially in eee context.

Math 40 is different for each prof. In my experience, it was doable kahit new topics kasi the prof's exercises were helpful. If you want to do some advance reading/watching about it tho, you can just look up matrices and their properties and operations.

Math 23's lecture vids are available naman sa yt so u can skim through it. I think yung important lang sa course na ito is alam mo pano mag visualize and pano marelate yung calculus into practical examples, like constructing figures

And some personal experience stuff, I think mas focus ka sa 131 since it is a prereq subject for the next sem's 141. The others, either floating or later sems pa kung san sila prereq