If the number 715 ■ 423 is divisible by 3 (■ denotes the missing digit in the thousandths place), then the smallest whole number in the place of ■ is _______.

What is the value of $$1 + {1 \over 4} + {1 \over {16}} + {1 \over {64}} + {1 \over {256}} + ......$$?

"By giving him the last __________ of the cake, you will ensure lasting ________ in our house today."

The words that best fill the blanks in the above sentence are

"Even though there is a vast scope for its __________, tourism has remained a/an _________ area."

The words that best fill the blanks in the above sentence are