*Challenge question #35 (31/10/2016)*

**Junior Question**

How many triangles are contained in this figure?

**Senior Question**

Suppose a group of numbers are written in a grid of rows and columns.

Amanda finds the *maximum* value of each *row*, and then finds the *minimum* of these values, which she calls $A$.

Bill finds the *minimum* value of each *column*, and then finds the *maximum* of these values, which he calls $B$.

Show that $A$ must be greater than or equal to $B$.