评述蔡元培的教育思想及其改革实践。

杨贤江写的马克思主义教育学著作是( )。

1918年鲁迅在《新青年》发表小说( )，批判封建礼教的吃人本质。

l computer and the spreadsheet (空白表格程序). Before the spreadsheet, business planning usually meant producing a single forecast. At best, you did a little sensitivity analysis around the projection. The spreadsheet ushered in a much more analytic approach to planning because every major line item could be pulled apart, its components and subcomponents analyzed and tested. You could ask what-if questions about the critical assumptions on which your business depended—for example, what if customers are more price-sensitive than we thought?—and with a few keystrokes, you could see how any change would play out on every aspect of the whole. In other words, you could model the behavior. of a business. Before the computer changed the nature of business planning, most successful business models were created more by accident than by elaborate design. By enabling companies to tie their marketplace insights much more tightly to the resulting economics, spreadsheet made it possible to model business before they were launched.

要负责tRNA及5S小分子rRNA的合成。然而，5.8S小分子rRNA的合成却是由合成18S、28S大分子rRNA的RNA聚合酶Ⅰ完成的。为什么?

。