After the USA introduces a tariff in the market for gigastraps, the price of gigastraps in the USA will:

I'm not sure what a gigastrap is or if it is just a some term made up for this question, but whenever an import tariff is set, the price of the product will increase. It doesn't matter if it is something simple as sugar, microchips, diamonds, cars, etc. It doesn't even matter if the product can be produced domestically or not, the price will still increase since the domestic producers will increase their price to match the increase in price of foreign goods. This is the reason why sugar is so expensive in the US, since the domestic producers charge extremely high prices because they know there is no way foreign sugar producers can compete with them due to the import tariffs and quotas.

answer: in the short-run firms will respond by raising the price of turkey.

explanation: initially the long-run equilibrium is at a price of $5 per pound of turkey and a quantity of 50 million pounds per year. now, when webmd claims that a protein found in turkey will increase your expected lifespan by 4 years. the consumers demand for turkey will increase at every price shifting the demand curve to the right from d1 to d2. while, there will be no change in the supply curve in the short-run as it is not possible for producers to adjust supply so quickly. as a result the new equilibrium will occur at a higher price and a higher quantity of turkey.

thus, in the short run firms will respond by increasing the price of turkey, selling more quantity at a higher price and earning economic profits.