Identify the mathematical operation and perform the calculation.

The image displays several multiplication problems, likely in a columnar format. However, the execution of these problems is incomplete or unclear in some instances. For example, the first problem shows '2.1' multiplied by '9.6', with some subsequent additions and a final result of '6', which doesn't seem to be the correct product of 2.1 and 9.6. Other problems are presented with the multiplicands and the line for the product, but the actual product is not written out. Here are the identified problems: 1. 2.1 \(\times\) 9.6 followed by partial steps and a written '6' below a line. 2. 1.6 \(\times\) 5.1 The result is not shown. 3. 7.7 \(\times\) 5.3 The result is not shown. 4. 9.9 \(\times\) 7.1 The result is not shown. Due to the incompleteness of the calculations, a full and accurate answer cannot be provided for all problems as presented in the image.