What is one example of a closed economy

The closed economy is a self sufficient economy. The countries following a closed economy system does not involve in the import and export of goods from other nations.  In these countries, all the goods are produced in the country is consumed within the country itself.

Brazil is a country, which can be said as closed economy as Brazil imports a very item from other nations. A Complete close economy system is not present in any country yet.

it is prolly d and c and f

the level of progesterone is low at the pre-ovulatory phase of the cycle but it gradually increases and the levels are high at the luteal phase. if pregnancy occurs, the level of progesterone will be high throughout the pregnancy.

if egg is fertilized and the mother gets pregnant, progesterone starts preparing the uterus for the implantation. it starts building up the lining of uterus and make it hostile of the period of pregnancy.