Non$-$GAAP Measures: Core Operating Earnings, Core Operating Margin, and Core Earnings Per Share

Our Consolidated Financial Statements are prepared in accordance with Generally Accepted Accounting Principles in the United States of America $($GAAP$),$ which we supplement with certain non$-$GAAP financial information. These non$-$GAAP measures should not be considered in isolation or as a substitute for the related GAAP measures, and other companies may define such measures differently $...$ Core operating earnings, core operating margin and core earnings per share exclude the impact of certain pension and other postretirement benefit expenses that are not allocated to business segments $...$ Management uses core operating earnings, core operating margin and core earnings per share for purposes of evaluating and forecasting underlying business performance. Management believes these core earnings measures provide investors additional insights into operational performance as unallocated pension and other postretirement benefit cost primarily represent costs driven by market factors and costs not allocable to U$.$S$.$ government contracts.

Required

a$.$ What are the non$-$GAAP measures reported?

b$.$ What GAAP measure is used in the reconciliation to compare to the non$-$GAAP measure?

c$.$ Why is this disclosure included in the MD&A section of the Form $10-$K and not in the notes accompanying the financial statements?

d$.$ Why is this non$-$GAAP measure reported?