Question

1. in 1964, stephanie kwolek and her team at dupont, a chemical company, were searching for a lightweight fiber that could replace steel in radial tires. kwolek’s research led to kevlar, a material five times stronger than steel by weight. the discovery process wasnt without obstacles. kwolek’s first attempt resulted in a thin, murky solution. her coworkers thought it should be discarded. kwolek persisted. she spun the solution in a spinneret, a machine used to remove liquid. when the solution was spun, it successfully produced a remarkably strong fiber: kevlar. now, kevlar is used in products such as bulletproof vests. after kwolek retired, she wanted to help students understand the complicated process of making materials like kevlar. she invented the nylon rope trick, a demonstration of how to make long strands of the chemical compound nylon.
2. match the problems with their solutions.
3. kwolek used a laboratory spinneret.

kwolek developed the nylon rope trick.
kwolek developed kevlar.

Explanation:

To solve the matching problem, we analyze each solution and its corresponding problem:

1. For the problem related to producing Kevlar from the murky solution: The text says "She spun the solution in a spinneret... it successfully produced... Kevlar". So "Kwolek used a laboratory spinneret" matches the problem of creating Kevlar from the initial solution.

1. For the problem related to helping students understand material - making: The text states "she wanted to help students understand... She invented the nylon rope trick". So "Kwolek developed the nylon rope trick" matches the problem of aiding student understanding.

1. For the problem related to finding a lightweight fiber to replace steel: The text says "Kwolek’s research led to Kevlar". So "Kwolek developed Kevlar" matches the problem of finding a steel - replacement fiber.

Answer:

1. Problem (related to producing Kevlar from murky solution) - Kwolek used a laboratory spinneret.
2. Problem (related to helping students understand) - Kwolek developed the nylon rope trick.
3. Problem (related to finding steel - replacement fiber) - Kwolek developed Kevlar.