 In production analysis under the financial constraints we are going to study economic cost. Previously we have studied various types of the costs. Total cost, average cost, marginal cost, sunk cost and all these type of the terms we are now very much familiar. Then what is the economic cost? As we have already studied that when we register certain types of the cost in certain ledger that is possible only and only when we assign certain monetary value to certain inputs or to the resources. So here the economic cost it requires that that monetary value it should be that much accurate or that it should be that much sufficient that it keeps the resource in the business process or it keeps the resource in our production process. If I say in simple words that any factor of production which we are using whether it is labour or capital means we are making a house we are making a building for a hotel or we have hired labour or if we say in this case if we say that a landlord or a cashier gives rent of one or two acres of land or he takes the water for an hour or two hours then it is giving the price. Now in the same way we assess the monetary value that actually how we are doing it. Mostly the prevalent rules that we see in the assessment of our ledger because competitive firms that they will be basically the price taker. So whatever will be the market price of that resource in the setup we will be paying it or any entrepreneur is paying it. So that market price either that is going to ascertain actual productivity of that resource and that is going to assess that either this resource will be kept in the production process or not. Or if we say that if a labourer or a labourer does not pay the right price then it will be difficult to keep it in the production process. And in the same way if the resource in the form of capital if we want to allocate the right resource for it if we want to do the right budgeting then it is only possible when it can be kept according to the right value. So the actual value assessment that is the other name of economic cost. Now when we talk about economic cost then we basically keep it in two parts. Now what are the two segments we have? One is the explicit cost and the other is the implicit cost. Explicit cost is a form of all the expenses that we spend in monetary terms in the form of money, in the form of dollar or in the form of currency at that time we spend according to that which we are getting from the market and we keep paying those resources according to that or we are evaluating them. And all these costs we are dealing with according to the proper cash transaction i.e. we are spending money and taking it. But some such expenses, some such costs that we have never assessed and what are those? Some such resources that we already have in our production process or some services that we have never assessed but they will be a part of our production process. So if we do not give proper valuation or assessment to these two then we will not be able to assess the complete economic cost of that production activity. Now if we do not do it then what will be the benefit or loss if we look at it. So in the rules of economics, we mostly, any resource that is a part of our production process we assess its marginal productivity. Now according to that marginal productivity we are producing two units the second one is producing four units or likewise we assess its productivity and by multiplying the market rate we assess it according to that and its labour, its wage, its capital, its rent. But now if we look at it from here then we are paying only according to that contribution which is becoming a part of the production procedure. But this is also a possibility that there are many of them whose alternative use we have. And whether we use it or use it somewhere else they can contribute more than that. So if we look at it in one way then about those resources we should also have an alternative or foregone value that whether it is better or less than that then we can do its proper economic valuation. And in the same way, if I tell you in simple words then it would be that if we give an electrical or software engineer who can give us an automation or can tell us about a system in the best form instead of that we can just send it to a place for data and Raj and even though we can have a data entry operator who can provide a junior level worker then we would be using them in the production process but not according to their capacity and they would be paying according to that so what will happen is that whenever tomorrow according to their capability they will get a job and they will get our resources. And likewise there can be a situation of capital. So this is why the economic cost it requires that we should properly value all the resources not only according to their tangible contribution to the business process but we should also include the valuation of certain implicit parts and the implicit system. And likewise there are many resources which we cannot find out or we are not doing assessment we know that they are contributing but we do not have proper valuation. Now we will see in detail how it is possible but economic cost will be equal to the sum of explicit cost and the implicit cost. And that is why whenever we have to measure the economic efficiency of a production process then we have to include these two costs. Thank you.