Any gain or loss should be recognized immediately.

Remember that when the null hypothesis is rejected, the results of the regression are said to be "statistically significant." In other words, the analyst has enough reason to assume that the results of the analysis are valid at the given level of significance. When the analyst fails to reject the null hypothesis, then the result is said to "not be statistically significant." While this specification may seem excessive, it is nevertheless important. The remaining answers are all correct.

First note that without imports, the price prevailing in the domestic market will satisfy 400 -
2 P = 100 + 4P, giving P = 50. The world price is 45 and with a 5% import tariff, it becomes 45 * 1.05 =
47.25. Since this price is lower than 50, there will continue to be imports and the price prevailing in the domestic market after the tariffs will equal 47.25.
Before the tariffs, the producers supply a quantity equal to 100 + 4 * 45 = 280 and domestic consumers demand 400 - 2 * 45 = 310 units. Thus, imports without the tariffs equal 310 - 280 = 30 units. With the tariff in place, the producers produce 100 + 4 * 47.25 = 289 units. The consumers demand 400 - 2 * 47.25 =
305.5 units. Thus, the imports now equal 305.5 - 289 = 16.5 units.

At a lower price the consumer will want to purchase more units. Consumer surplus will increase because additional units with consumer surplus will be purchased and earlier units will each have a larger consumer surplus.