Why An externality exists when a person makes a choice that affects other people in a way that is not accounted for in the market price. An externality can be positive or negative but is usually associated with negative externalities in environmental economics. For instance, water seepage in residential buildings occurring in upper floors affect the lower floors?

If you need some support data, here it is:

Outline a strategy that your opponent can use to achieve this. Briefly describe the calling mechanisms just mentioned and discuss why most modern programming languages provide only call by value. [8 marks] (c) Discuss the reasons why languages such as Fortran, Algol and PL/I designed in 1950s and 1960s are less widely used than languages designed in the last 20 years. [5 marks] By considering storage layouts, explain why the former assignment is always valid and the latter sometimes invalid. [8 marks] (a) A new programming language has the notion of "statically scoped exceptions" in which the program exception foo; void f() { try { void g() { raise foo; } try { g(); } except (foo) { C2 } } except (foo) { C1 } } would execute C1 rather than C2 as the former was in scope at the raise point. [20 marks] 5 [TURN OVER CST.2005.8.2 10 Introduction to Security (b) Explain briefly mechanisms that software on a desktop computer can use to securely generate secret keys for use in cryptographic protocols. [5 marks] Approximately how large must n be at least for your opponent to have a greater than 75% chance of on P ensures that P|newa Q R2 for some R2 with R1 R2? Justify your answer. [5 marks] We might expect that this model would be implemented in a relational schema such as S(A, BA), T(AC, Amount), and R(A, C). However, the database implementor has noticed that a very common and expensive query is this: given an A-value a, find the sum of all Amount values for records in T related to this a value in S. Therefore, the implementor has decided to "optimise" the database and replace table S with S Your function should run in linear time in the size of the tree. [4 marks] Which of the following sets of functional dependencies may hold in R?