Aspinner is divided into 10 equal sections numbered 1 through 10. if the arrow is spun twice, what is the probability the first number will be even and the second number will be a 7

What is the number 321,000,000 in scientific notation? also what is the number? ?

Match the scale and the actual area to the area of the corresponding scale drawing. scale: 1 inch to 4 feet actual area: 128 square feet scale: 1 inch to 7 feet actual area: 147 square feet scale: 1 inch to 8 feet actual area: 256 square feet scale: 1 inch to 5 feet actual area: 225 square feet area of scale drawing scale and actual area scale drawing area: 3 square inches arrowright scale drawing area: 8 square inches arrowright scale drawing area: 4 square inches arrowright scale drawing area: 9 square inches arrowright

Events a and b are independent. the probability of a occurring is 2/5. the probability of b occurring is 1/4. what is p(a and b)?