The following table shows National Income (Y), Consumption (C), Investment (I), Government Spending (G), Exports (X) and Imports (M) for 2018 and 2019 - Leaving Cert Economics - Question b - 2020

For 2019, we use the values provided:

$Y = C + I + G + X - M$

Substituting the known values for 2019:

$Y = 105,000 + 55,000 + 60,000 + 65,000 - 90,000$

Calculating yields:

$Y = 105,000 + 55,000 + 60,000 + 65,000 - 90,000 = 250,000$

Thus, the level of National Income in 2019 is €250,000.

The marginal propensity to import (MPM) is defined as the proportion of any additional income that is spent on imported goods and services. It quantifies how much of an increase in income will lead to an increase in imports.

To calculate MPM for the given data, we will use the formula:

MPM = rac{ ext{Change in imports}}{ ext{Change in national income}}

Change in imports from 2018 to 2019: $65,000 - 60,000 = 5,000$

Change in National Income from 2018 to 2019: $250,000 - 200,000 = 50,000$

Thus, substituting into the equation gives:

MPM = rac{5,000}{50,000} = 0.1

So, the marginal propensity to import (MPM) is 0.1.

The formula for the multiplier (k) is:

k = rac{1}{MPS}

First, we need to calculate the marginal propensity to save (MPS):

MPS = 1 - MPM = 1 - 0.1 = 0.9

Now, we can compute the multiplier:

k = rac{1}{0.9} = 1.11

This means that for every €1 injected into the economy, the total effect on National Income will be approximately €1.11. The significance of this figure indicates that any increase in government spending will have a multiplied effect on the overall economy.

National debt is described as the total/cumulative amount of government domestic and foreign borrowing which remains outstanding. It sums up all past deficits that have not been repaid, representing the financial obligations of a country.

The agency responsible for managing Ireland’s national debt is the National Treasury Management Agency (NTMA).

One other function of the NTMA is to provide financial advice and possible funding for government projects. This involves managing Ireland's cash reserves and ensuring that the government can meet its fluctuating funding needs.

1. Opportunity costs involved / Loss of public services: With more funds tied up in debt repayments, government spending on essential public services may drop, leading to deterioration in services such as health and education.
2. Increased burden on future taxpayers: High national debt means that future governments will face greater obligations to meet repayments, potentially leading to higher taxes or reduced services.
3. Loss of economic sovereignty / damage Ireland's credit rating: High levels of national debt can hurt Ireland's reputation with lenders and may limit the country’s ability to borrow in the future or lead to higher interest rates.