In 2018, NB Inc.’s federal taxable income was $242,000. Compute

In 2018, NB Inc.’s federal taxable income was $242,000. Compute the required installment payments of 2019 tax in each of the following cases: 

a. NB’s 2019 taxable income is $593,000. 

b. NB’s 2019 taxable income is $950,000. 

c. NB’s 2019 taxable income is $1,400,000.