Need help with Java Chapter 9 exercise.

1. What is the value of the variable named cap after the code that follows is executed?

StringBuilder name = new StringBuilder("Thomas");

int cap = name.capacity();

a.	6	d.	22
b.	10	e.	28
c.	16

What is the value of s1 after the code that follows is executed?

StringBuilder title = new StringBuilder();

title.append("The Basics of OOP");

title.delete(0, 13);

String s1 = title.toString();

a.	"The Basics of OOP"	d.	"OOP"
b.	"The Basics of"	e.	"The Basics of "
c.	" OOP"

2. What is the value of s1 after the code that follows is executed?

StringBuilder s1 = new StringBuilder();

s1.append("115-88-9525");

s1.deleteCharAt(4);

a.	115-8-9525	c.	115-88-9525
b.	11588-9525	d.	115889525

3. The equality operator (==) checks whether

a.	two String variables contain the same characters
b.	two Strings variables refer to the same String object
c.	both a and b
d.	none of the above

4. To make sure your code is thread-safe, you would use the

a.	StringBuilder class	c.	both a and b
b.	StringBuffer class	d.	none of the above