(a) Avoiding unnecessary memory allocation and deallocation is one of the main recommendations in optimising performance of Android programs. Explain why this is and describe three measures to aid this.

(b) Even the composition of a layout can affect performance of an app. Explain, with an example.

(c) Event listeners in Android make extensive use of Anonymous classes. Why is this and explain how this functionality is used in code through an example.

(d) Give three mechanisms for the transfer of data from one activity to another. Discuss one in detail, with diagrams to illustrate.

(e) Virtual sensors can be used to gain a highly accurate representation of what is needed to be shown by an app. How is this possible, giving an example.