1. The capacity of a rectangular water tank is 320 liters. The bottom of this water tank is a square with a side length of 8 decimeters. What is the height of the water tank?

The classroom of Class 2.2 (1) is on the second floor (* * * fourth floor). The classroom is 10 meter long, 6 meters wide and 4 meters high, and the door and window area is 19.6 square meters. If the interior wall is painted with 0.25 kilograms of paint per square meter, how many kilograms of paint does * * need?

3. A rectangular iron sheet with a length of 26 cm and a width of 16 cm was cut from the four corners and welded into an open iron box. What is the volume of this iron box?

brief introduction

In mathematics teaching, practical problems including some mathematical relations (such as quantitative relations and geometric figure position relations) are described by language or words, and the problems formed in this way are called application problems. Any application problem contains two parts. The first part is known conditions (conditions for short), and the second part is seeking problems (problems for short). The conditions and problems of application questions constitute the structure of application questions.