Thvuvugufugy i need help pls i beg​

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

1c) the number 131 is a term in the sequence defined by the explicit rule f(n)=5n-4. which term in the sequence is 131? 2a) write the first four terms of the function f(n)=n^2-1 2b) what is the 10th term of the sequence defined by the explicit rule f(n)=n^2-1 2c) the number 224 is a term in the sequence defined by the explicit rule f(n)=n^2-1. which term in the sequence is 224?

What is the radius of a circle with an area of 78.5 cubic inches? use 3.14 for pie