1. 다음 글에서 언급된 ultrasonic sound waves의 용도와 거리가 먼 것은?

What can you do with ultrasonic sound waves? Plenty! One of their early uses was in locating submarines. They are still used for the same purpose, but now they are also used to find the depth of the ocean and to locate schools of fish and objects in the deep sea. A pulse of ultrasound is sent out into the water, reflected from some object and then received back at the ship. The time taken for the pulse to return is measured and used to calculate the distance of the object from the ship.

①잠수함의 위치를 찾아내기

②배의 속도를 빠르게 하기

③바다의 깊이를 알아내기

④어군을 탐지해내기

⑤바다 속 물체와 배 사이의 거리 측정하기

2. 다음 글을 읽고 빈칸에 가장 적절한 것을 고르시오.

Ultrasound can be used in for a number of purposes as well. It can help find flaws in metals. A pulse of ultrasound is aimed at the metal and any flaws reflect the pulse, allowing their size and location to be determined. Ultrasound is also used for delicate cleaning. Objects are placed in a liquid and subjected to ultrasound, which loosens the dirt particles.

①industry②medicine③art

④dry cleaning⑤construction