I will mark you as the brainiest if you get this correct Thx so much xxx

When are two distinct non vertical lines parallel

A) if $50000 is invested in a bank account that pays 9.3% of interest compounded on a six-monthly basis, how much money will be in the account after 3 and 12 years? b) if matusalen's father had put $2.0 in the bank when he was born and there, how long would matusalen have had to his death (969 years later) if the interest was 7% per year composed each month and weekly?

Which of the following is most likely the next step in the series? a3z, b6y, c9x, d12w, е15v, f18u