1. A rectangular tank with a length of 2.1 meters and a width of 1.5 meters is half-filled with water. If 630 liters of water are added to the tank, how much will the water level rise?

2. A tank measuring 21 decimeters in length, 11 decimeters in width, and 6 decimeters in depth is half-filled with water. If 100 solid spheres, each with a diameter of 21 centimeters, are submerged into the tank, by how many decimeters will the water level rise?

3. A rectangular water tank is 2.1 meters long and 1.5 meters wide, and is currently half full of water. If 630 liters of water are added to the tank, calculate and write how much the water level (depth) will rise.

4. A trough measuring 21 decimeters in length, 11 decimeters in width, and 6 decimeters in depth is half full of water. If 100 iron spheres, each with a diameter of 21 centimeters, are completely submerged in the trough, determine how much the water level will rise in decimeters.

5. If a pump can fill 37,400 liters of water in 1 hour, how much time will it take to raise the water level by 17 decimeters in a rectangular tank with a length of 18 meters and a width of 11 meters?

6. A tank that is 21 decimeters long, 11 decimeters wide, and 6 decimeters deep is half-filled with water. If 100 solid iron spheres, each with a diameter of 21 centimeters, are fully submerged in the tank, calculate how much the water level will rise (in decimeters).

7. A rectangular pond is 20 meters long and 18.5 meters wide, and contains water to a depth of 3.2 meters. A pump that can irrigate 160 kiloliters of water per hour is used to remove all the water from the pond. Calculate and write how long it will take to pump out all the water. If this water is then used to irrigate a field with embankments measuring 59.2 meters in length and 40 meters in width, calculate and write the depth of water that would cover the field. [Note: 1 cubic meter = 1 kiloliter]

8. The base length and width of a rectangular reservoir are 15 meters and 12 meters respectively. Water is filled into the reservoir from a nearby pond using a pump. If the pump can fill 36,000 liters of water per hour, then how long will it take for the pump to fill the reservoir up to a height of 7.2 decimeters? [Note: 1 liter = 1 cubic decimeter]

9. A cuboidal oil tanker measuring 4 meters in length, 2.5 meters in width, and 10 meters in depth is filled with an additional 12,000 liters of oil. By how many decimeters will the oil level rise?

(a) 20 decimeters. (b) 15 decimeters. (c) 12 decimeters. (d) 22 decimeters.

10. A rectangular container has a base in the shape of a rectangle with a length of 60 cm and a width of 45 cm. The container has a height of 20 cm and is half-filled with water. Determine the side length of a metallic cube that, when placed in the container, will cause the water level to reach the brim.

11. From a completely water-filled cubical tank, 75 buckets of equal size are taken out, after which \(\frac{2}{5}\) of the tank remains filled with water. If each edge of the tank is 1.5 meters long, how much water does each bucket hold in liters?

12. The English translation is: "A cube-shaped tank completely filled with water becomes \(\frac{1}{3}\) full after removing 64 equal-sized buckets of water. If the length of each side of the tank is 1.2 meters, how much water does each bucket hold (in liters)?"

13. A roof measuring 13 meters in length and 11 meters in width had its drainage pipe closed during rainfall. After the rain, it was found that water had accumulated to a depth of 7 centimeters on the roof. The pipe through which the water drains has a diameter of 7 centimeters and discharges water in the form of a cylindrical stream at a rate of 200 meters in length per minute. Determine how long it will take for all the water to drain out once the pipe is opened.

14. The daily water requirements of three families living in three flats are 1200 liters, 1050 liters, and 950 liters respectively. A tank needs to be installed such that, even after meeting these demands, 25% of the total water remains in reserve. A space of 2.5 meters in length and 1.6 meters in width is available for the tank. Determine how deep the tank should be.

15. The rectangular village field has a length of 20 meters and a width of 15 meters. To install pillars at the four corners, four cube-shaped holes of 4 meters in length were dug and the removed soil was spread evenly over the remaining area of the field. Calculate how much the surface level of the field will rise.

16. From a completely filled cube-shaped water tank, 64 equal-sized buckets of water are taken out, leaving the tank one-third full. If the length of one edge of the tank is 1.2 meters, calculate and write how many liters of water each bucket can hold.