On the verge of a mental breakdown someone help me solve thiss

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?

If a is a nonzero real number then the reciprocal of a is

What is the length of the midsegment of a trapezoid with bases of length 15 and 25 ?