For completing the task correctly you will receive 1 point. It takes approximately 5 minutes.

To complete task 9 in computer science you need to know:

• I - volume of information
• to store a bitmap you need to allocate memory I = N i bits, where N– number of pixels and i– color depth (encoding bit depth)
• number of image pixels N calculated as the product of the image width and height (in pixels)
• coding depth is the number of bits allocated to store the color of one pixel
• The volume of a music file is calculated using formula I = f*r*k*t, Where f– sampling frequency, r– resolution (encoding depth), k– number of channels, t – playing time
• channel B capacity = f*r*k

Tasks for training

Task No. 1

An automatic camera produces raster images size 640x480 pixels. In this case, the size of the image file cannot exceed 320 KB, and no data packaging is performed. What is the maximum number of colors that can be used in a palette?

Task No. 2

To store an arbitrary raster image of 256×1024 pixels in size, 64 KB of memory is allocated, and for each pixel a binary number is stored - the color code of this pixel. For each pixel, the same number of bits are allocated to store the code. Data compression is not performed. What is the maximum number of colors that can be used in an image?

Task No. 3

What is the minimum amount of memory (in KB) that must be reserved to be able to store any 512-by-128-pixel bitmap image, assuming that the image can use 512 different colors? In your answer, write down only an integer; there is no need to write a unit of measurement.

Task No. 4

The musical fragment was recorded in stereo format (two-channel recording), digitized and saved as a file without using data compression. The size of the resulting file is 100 MB. The same piece of music was then re-recorded in mono and digitized at a resolution 3 times higher and a sampling rate 5 times lower than the first time. No data compression was performed. Specify the file size in MB of the resulting rewrite. In your answer, write down only an integer; there is no need to write a unit of measurement.

| Computer Science and Information and Communication Technologies | Preparation for the Unified State Exam | Control training tasks

Control training tasks

Part 1

Task 9

The answers to tasks 1 – 23 are a number, a sequence of letters or numbers that should be written in ANSWER FORM No. 1 to the right of the number of the corresponding task, starting from the first cell, without spaces, commas and other additional characters. Write each character in a separate box in accordance with the samples given in the form.

Example 1

What is the minimum amount of memory (in KB) that must be reserved to be able to store any 64x64 pixel bitmap image, assuming that the image can contain 256 different colors? In your answer, write down only an integer; there is no need to write a unit of measurement.

Example 2

To store an arbitrary raster image of 1024x1024 pixels in size, 512 KB of memory is allocated, and for each pixel a binary number is stored - the color code of this pixel. For each pixel, the same number of bits are allocated to store the code. Data compression is not performed. What is the maximum number of colors that can be used in an image?

Answer: ___________________________.

Example 3

The automatic camera produces raster images of 640x480 pixels. In this case, the size of the image file cannot exceed 320 KB, and no data packaging is performed. What is the maximum number of colors that can be used in a palette?

. Information coding, volume and transmission of information: demo version of Unified State Exam Informatics 2019; state final exam 2019; training versions of the Unified State Exam in computer science, thematic test tasks and tasks from the computer science simulator 2019

✍ Solution:

• Let's remember the basic formula for the volume of an image file:

I = m * n * i

m, n — resolution (width and height in pixels)
i — color coding depth

We express all values ​​in powers of two:

200|2 100|2 50 |2 25 | 25 * 2 3

Permission:

25 * 2 3 * 2 8 = 25 * 2 11

Let's substitute all the values:

i * 25 * 2 11

Since i must be less than the obtained value, then i=10.

Let's count the number of colors:

colors = 2 i = 2 10 = 1024

Result: 1024

9 Unified State Exam 2019 tasks for training

Option No. 3, 2019 (10 options), S.S. Krylov, T.E. Churkina:

800×2800 700 KB

Which

Answer: 4

Option No. 4, Model exam options 2019 (10 options), S.S. Krylov, T.E. Churkina:

An automatic camera produces raster images of size 1000×1600 pixels. The same number of bits are used to encode the color of each pixel, and the pixel codes are written to the file one after the other without gaps. The size of the image file cannot exceed 2100 KB excluding the size of the file header.

Which maximum number of colors can it be used in a palette?

Answer: 1024

Option No. 8, Model exam options 2019 (10 options), S.S. Krylov, T.E. Churkina:

Which minimum memory size (in KB) needs to be reserved so that any bitmap size can be saved 1280 x 80 pixels provided that the image may be used 64 different colors? In your answer, write down only an integer; there is no need to write a unit of measurement.

Analysis of task 9 of the Unified State Exam 2018 in computer science and ICT from the demo version. This is a task of a basic level of difficulty. The approximate time to complete the task is 5 minutes.

Checked content elements:
— Ability to determine the speed of information transmission at a given bandwidth channel, the amount of memory required to store sound and graphic information.

Task 9

The automatic camera produces raster images of 640x480 pixels. In this case, the size of the image file cannot exceed 320 KB, and no data packaging is performed. What is the maximum number of colors that can be used in a palette?

Answer: ________

Analysis of task 9 of the Unified State Exam 2018 in computer science

The volume of a raster image is calculated as the product of the number of pixels in the image and the amount of memory i , necessary to store the color of one pixel

In our case

640 480 i ≤ 320 1024 8 bits

i ≤ 320 1024 8/(640 480),

since a bit can only be an integer, we get

i=8(in our problem it is said that the size of the image file cannot exceed 320 KB, therefore, we cannot round up! The resulting value i round down to 8 bits!)

To do this we use the formula N=2 i

N = 2 8 = 256

This means that you can use no more than 256 flowers.

The author of the assignments is a leading specialist who is directly involved in the development of control measuring materials for the Unified State Exam.
Typical test tasks in computer science contain 14 variants of sets of tasks, compiled taking into account all the features and requirements of the Unified State Exam in 2019. The purpose of the manual is to provide readers with information about the structure and content of the 2019 KIM in computer science, the degree of difficulty of the tasks.
The collection contains answers to all test options, provides solutions to all tasks of one of the options, as well as solutions to problems in part 2.
The manual is intended for teachers to prepare students for the computer science exam, as well as for high school students for self-preparation and self-control.

Examples.
The automatic camera produces raster images measuring 640 x 480 pixels. In this case, the size of the image file cannot exceed 170 KB, and no data packaging is performed. What is the maximum number of colors that can be used in a palette?

Performer A16 converts the number written on the screen.
The performer has three teams, which are assigned numbers:
1. Add 1
2. Add 2
3. Multiply by 2
The first of them increases the number on the screen by 1, the second increases it by 2, the third multiplies it by 2.
The program for performer A16 is a sequence of commands.
How many programs are there that convert the original number 3 into the number 12 and at the same time the program's computation path contains the number 10?
A program's computation trajectory is a sequence of results from the execution of all program commands. For example, for program 132 with the initial number 7, the trajectory will consist of the numbers 8, 16, 18.

Free download e-book in a convenient format, watch and read:
Download the book Unified State Examination 2019, Computer Science, 14 options, Model test tasks, Leshchiner V.R. - fileskachat.com, fast and free download.

• I will pass the Unified State Exam, Computer Science, Typical tasks, Leshchiner V.R., Krylov S.S., Ushakov D.M., 2019
• Unified State Examination, Computer Science, 11th grade, Preparing for the final certification, Leshchiner V.R., Krylov S.S., Yakushkin A.P., 2020
• Unified State Exam 2020, Computer Science, 16 options, Typical versions of exam tasks from Unified State Exam developers, Leshchiner V.R.
• Computer Science, Unified State Exam, Preparing for the final certification, Leshchiner V.R., Krylov S.S., Yakushkin A.P., 2020

The following textbooks and books.