Could someone help me find the height of this 2-d figure after being rotated about the line?

What is the most accurate measurement of 1 pound

Asandwich shop has 18 tables. each table seats up to 4 people. to find the greatest number of people that can be seated, you can solve p4 ≤ 18. which step is the best way to solve the inequality? plz asap i repeat plz

What are the solutions of the equation x4 + 6x2 + 5 = 0? use u substitution to solve.