JJ is planning for the future and wants to save $$50,000$ for a down payment on a house. He currently

has $$10,000$ to invest, and the town bank offers $3\%$ interest on all accounts. How long would it take

JJ to reach his goal if the bank...

$[$Note: Round your final answer based on the compounding period.$]$

$($a$)$ uses simple interest?

$($b$)$ compounds interest quarterly?

$($c$)$ compounds interest monthly?

$($d$)$ compounds interest continuously?