Java Taskbook Level 5.9

Display the following pyramid on the screen:

xx
xxxx
xxxxxx
xxxxxxxx
xxxxxxxxxx

Given an array:

{
	"123",
	"213",
	"321",
}

Replace the characters "1" with "0" in each line:

{
	"023",
	"203",
	"320",
}

Given a number:

int num = 12345;

Double the digits in this number:

1122334455

Given an array:

{
	"text1",
	"text2",
	"text3",
	"text4",
	"text5"
}

Make a line out of this array so that each element of the array is on a new line:

"""
	text1
	text2
	text3
	text4
	text5
"""