A piece of copper is heated to 90°C and then lowered into a beaker of water at 20°C.

The copper transfers 3040 J of energy to the water before it is removed.

The temperature of the copper after it is removed is 50°C.

The specific heat capacity of copper is 380 J/kg °C.

Calculate the mass of the copper.

20kg

Explanation:

heat lost by copper=heat gained by watter

a.metals can become magnetic if they have many spinning electrons that create magnetic fields.d.only some metals are attracted by magnets; these metals are called ferromagnetic.

d.wrapping an insulated wire around a metal with ferromagnetic properties and applying an electric current.

there is no correct list among the choices you've provided.

the list might look something like this:

-- baby human

-- piccolo

-- flute

-- soprano singer

-- trumpet

-- tenor singer

-- trombone

-- baritone singer

-- baritone horn

-- bass singer

-- tuba

since i had to make up the list myself, i made it easy on myself, and i didn't try to shuffle the string instruments and woodwinds into it too.