Can universities make their sums work?  As students nervously receive their A-level results, many of the universities they'll enrol in are facing their own concerns over what's next...     Academics have warned that years of underfunding and a lack of lucrative international students at British universities after visa changes risks the sector's ability to provide top-class education and, for some institutions, whether they'll be able to keep teaching at all.    On this episode, Niall Paterson is joined by two university vice-chancellors, Professor Jane Harrington at Greenwich and Professor David Maguire at East Anglia, to hear the realities and challenges faced by universities across the country.    Plus, our business correspondent Paul Kelso explains why higher education is facing the crisis it's in now.  Producer: Soila Apparicio  Editor: Paul Stanworth