Answer:
Decrease
Increase
Frictional unemployment
b. Improving a widely used job-search website so that it matches workers to job vacancies more effectively
Explanation:
If the price of steel falls, the number of steel producing firms would reduce. As a result, the demand for labor among steel-producing firms would fall.
Steel is now cheaper, so the demand of steel by automobile companies would rise and the production of car would rise. More labour would be needed to make more cars and as a result demand for Labour in the car industry would rise.
Frictional unemployment occurs when Labour leaves his current and unemployment and searches for a new one. The period between when Labour is unemployed and searching for a new job is known as frictional unemployment.
Improving a widely used job-search website so that it matches workers to job vacancies more effectively would reduce the search period and reduce frictional unemployment.
I hope my answer helps you