Please help me it’s due today and I don’t understand

Select all the correct answers. what is 221,000,000,000,000,000,000 expressed in scientific notation?

The weights of broilers (commercially raised chickens) are approximately normally distributed with mean 1387 grams and standard deviation 161 grams. what is the probability that a randomly selected broiler weighs more than 1,425 grams?

Afamily has five members. a mom, a dad, two sisters, & a brother. the family lines up single file. what is the probabillity that the mom is at the front of the line