Which one of these variables is a binomial random variable?

1. You observe the gender of the next 300 babies born at a local hospital. The random variable represents the number of girls.

2. You roll a die 650 times. The random variable represents the number that appears on each roll of the die.

3. You spin a number wheel hat has 17 numbers 250 times. The random variable represents the winning numbers on each spin of the wheel

. 4. You test four pain relievers The random variable represents the pain reliever that is most effective.

5. Testing a pain reliever using 840 people to determine if it is effective. The random variable represents the number of people who find the pain reliever to be effective