Read the short email about a new machine. Then, answer the three multiple-choice questions below.

To: Maintenance Team From: Ms. Petrova, Supervisor Subject: New Grinder Safety and Operation

Dear Team,

We have a new grinder in the shaping department. This is a powerful tool, so safety is compulsory. Before starting any operation, you must wear all PPE: Safety glasses and ear protection are essential because the machine makes noise and fine metal dust.

When using the grinder, you must check the dimensions of the part first using the caliper to ensure quality. If the surface of the part is rough, you can use the grinder to make it smooth. If you find any problem or hazard with the tool, you must immediately report it to me or fill out an accident report form. Remember to check the electricity with the multimeter before starting maintenance.

What piece of PPE is most important because the grinder makes noise?