Random command! Returns the sum of the elements of a matrix. The cumSum( command gets the cumulative sum of each column in the matrix, adding the value of the previous element to the next element, and repeating this for each consecutive element in the column. When the cumSum( command is finished, the last element in each column will contain the sum of that column.
AIG: What does this US giant do? American International Group (AIG) is one of the world's biggest insurance firms, but it has fallen spectacularly from grace in recent months. Although it provides services to millions of people across the world, it recently announced the biggest quarterly loss in corporate history.
Glucagon works along with the hormone insulin to control blood sugar levels and keep them within set levels. Glucagon is released to stop blood sugar levels dropping too low, while insulin is released to stop blood sugar levels rising too high. (c) Explain how a negative feedback system regulates glucagon levels.