Which of the following statements is CORRECT?

a$.$ Most rapidly growing companies have positive free cash flows because cash flows from existing operations generally exceed fixed asset purchases and changes to net operating working capital.

b$.$ Managers should be less concerned with free cash flow than with accounting net income. Accounting net income is the "bottom line" and represents how much the firm can distribute to all its investors$-$both creditors and stockholders.

c$.$ Free cash flow $($FCF$)$ is defined as follows:

$FCF=$EBIT$(1-T)$

Depreciation

Capital expenditures required to sustain operations

Required changes in net operating working capital.

d$.$ Free cash flow $($FCF$)$ is defined as follows:

$FCF=$EBIT$(1-T)+$ Capital expenditures.

e$.$ Changes in working capital have no effect on free cash flow.