Interest and Penalties. In $2018,$ Paul, who is single, has a comfortable salary from his job

as well as income from his investment portfolio. However, he is habitually late in filing his

federal income tax return. He did not file his $2018$ income tax return until December $4,$

$2019($due date was April $15,2019)$ and no extensions of time to file the return were filed.

Below are amounts from his $2018$ return:

Paul sent a check with his return to the IRS for the balance due of $$5,400.$ He is re$-$

lieved that he has completed his filing requirement for $2018$ and has met his financial

obligation to the government for $2018.$

Has Paul met all of his financial obligations to the IRS for $2018?$ If not, what addi$-$

tional amounts will Paul be liable to pay to the IRS?