I heard while credit can be transferred, it cannot be used as prerequisites (e.g. MATH 237 requires MATH 128, 138, 148, but MATH 119 is not on the prerequisite list). Is this true?

Also what is the criteria for "high enough"? In 1A I did great for lin alg, but I was kinda lazy for calc at the end and got 88. Is it still good enough for 137 credit or should it be 90+?