A. All methods in an interface must be . b. All variables in an interface must be .
c. Interfaces cannot be .
d. Interfaces cannot contain methods.
e. Interfaces are considered to be classes.

Assume the existence of a bankaccount class. define a derived class, savingsaccount that contains two instance variables: the first a double, named interestrate, and the second an integer named interesttype. the value of the interesttype variable can be 1 for simple interest and 2 for compound interest. there is also a constructor that accepts two parameters: a double that is used to initialize the interestrate variable, and a string that you may assume will contain either "simple", or "compound", and which should be used to initialize the interesttype variable appropriately. there should also be a pair of functions getinterestrate and getinteresttype that return the values of the corresponding data members (as double and int respectively).

1. you have a small business that is divided into 3 departments: accounting, sales, and administration. these departments have the following number of devices (computers, printers, etc.): accounting-31, sales-28, and administration-13. using a class c private network, subnet the network so that each department will have their own subnet. you must show/explain how you arrived at your conclusion and also show the following: all available device addresses for each department, the broadcast address for each department, and the network address for each department. also, determine how many "wasted" (not usable) addresses resulted from your subnetting (enumerate them).

An environmental protection agency study of 12 automobiles revealed a correlation of 0.47 between engine size and emissions. at 0.01 significance level, can we conclude that there is a positive association between the variables? what is the p value? interpret.