“Transaction costs associated with divesting and replacing existing fossil fuel assets in university endowments are likely to be substantial. Focusing on a sample of 30 universities, including large, medium-sized, and small endowments, conservative estimates of these transaction costs range between 60 basis points and 269 basis points for large endowments, between 25 basis points and 180 basis points for medium endowments, and between nine basis points and 124 basis points for small endowments”