2011年JAVA认证模拟题第二阶段（10）

会计考友

　　Q28.What methods does JAVA define in the java.lang.Math class specifically for trigonometric calculations? Select all valid answers.
　　a. cos()
9 x& D1 L" F& c+ R/ w, C　　b. asin()
  P/ I+ M) i6 h* M- A6 _& V$ X　　c. arctan()
2 z7 T* V: E& W" I2 M0 u  x　　d. sine()
　　Q29.Imagine that there are two exception classes called Exception1 and Exception2 that descend from the Exception class. Given these two class definitions,
  w/ W# P/ o. i6 W% `7 }　　1. class First {
: Y8 t5 ~- {/ r* N- k& j/ G6 C　　2. void test() throws Exception1, Exception2 { . . . ｝
　　3. ｝
5 V9 P1 D  ?5 C4 ?: K  a　　4. class Second extends First {
7 @4 s# h  o7 v- [) K　　5. void test() { . . . ｝
　　Create a class called Third that extends Second and defines a test() method. What exceptions can Third's test method throw? Select all valid answers.
, T! X+ s/ `4 H8 R　　a. Exception1
1 ^+ V( D" y. P* j　　b. Exception2
　　c. no checked exceptions
7 ~* ^% ?. M2 \6 |) O! O% O　　d. any exceptions declared in the throws clause of the Third's test() method.
　　Q30.Given these code snippets,
　　1. Boolean b1 = new Boolean(true);
: P1 _! _- ^6 H* v　　2. Boolean b2 = new Boolean(true);
$ s8 _  N' \; B* G5 z　　which expressions are legal JAVA expressions that return true? Select all valid answers.
　　a. b1 == b2
6 \5 x5 O& Y" I2 p$ n4 ?　　b. b1.equals(b2)
　　c. b1 & b2
　　d. b1 || b2
; ?) ]7 j! w: m+ |' D9 o( L0 ~　　28. ab
　　29. c
; ~7 z9 x: @( X　　30. b