Cash budgets do not include cash inflows from long-term sources such as bond issues, as they focus on short-term cash flows. Cash budgets also do not include financial expenses such as interest and dividend payments, which are not part of operational cash flow. While depreciation expense is not explicitly included in cash budgets, its effects are implicitly accounted for in estimated tax payments since depreciation reduces taxable income. Therefore, the correct answer is "Both a and b above."