11 DigiTech - Unit 2.1.1 and 2.1.2 test

Part of a bitmap image is shown below in Fig 1:

a) Using the example in Fig 1, explain how a bitmap image is stored on a computer. [3]

b) Explain the impact of increasing the number of colours in the image used in Fig.1 [2]

Describe the following compression methods:

a) Lossy [2]

b) Lossless [2]

Sonny uses his laptop computer to record an audio track of himself playing the guitar.

a) Identify the industry standard sample rate Sonny should use. [1]

b) Outline what happens when the computer converts the music into a file. [2]

c) Sonny increases the sample rate his laptop is using to record his guitar.

Explain two effects this will have on Sonny’s recording. [4]

Emily is creating a film for a school project using a digital video camera and will transfer the videos to a computer for editing.

The computer 2GB of storage free.

Calculate the number of videos that could be stored on the computer if each video was 200MB in size. You must show your working. [2]

1. A file size has a size of 72,000,000,000 bits.

Calculate the file size in megabytes and gigabytes. You must show your working.

a) Megabytes [1]

b) Gigabytes [1]

Calculate how many bits there are in a file with a size of 20 megabytes.

You must show your working.

supermarket checkout uses a barcode reader to store and read items being scanned. The barcode reader users solid-state storage. Solid-state storage can be used as a secondary storage.

a) Explain why secondary storage is needed. [2]

b) Explain two reasons why solid-state storage is the most suitable for a barcode reader. [4]

c) Name two other types of solid-state storage. [2]

There are three different types of secondary storage: optical, magnetic and solid state.

Identify each of these devices with correct type.

A number of characteristics have to be considered when deciding what is the best medium of storage to be used.

State four storage characteristics.

St. Ignatius Catholic School are considering whether to move all of their data from the local server on site to a cloud-based service provider.

Discuss the issues the school should consider before making a decision.

Identify the stages in which the following tasks are carried out in System Development Life Cycle (SDLC).

Explain the purpose of operating system and identify three functions carried out by operating system [4]

Identify software category of the following Apps: