Which of the following is a minimum good practice requirement on the part of the operator while performing a bubble leak test?

Develop a vacuum of at least 124 kPa (36.5 in. Hg) on the specimen.

Be able to maintain pressure on the specimen for at least 0.17 h.

Be able to place the operator's eyes within 61 em (24 in.) of the test surface when observing the solution for leakage.

Have 20/20 vision without correction (glasses) in both eyes.