Please help me and tell me how to do it

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

Ahighway between points a and b has been closed for repairs. an alternative route between there two locations is to travel between a and c and then from c to b what is the value of y and what is the total distance from a to c to b?

What are the intercepts of x^2+y-9=0