(giving brainlist) Which are features of the structure of a polymer? Select all that apply.

usually three atoms large.

always repeats the same unit

can be thousands of atoms large

made of smaller molecules

often made from repeating units

100 grams of molten lead (600°c) is used to make musket balls. if the lead shot is allowed to cool to room temperature (21°c), what is the change in entropy (in j/k) of the lead? (for the specific heat of molten and solid lead use 1.29 j/g⋅°c; the latent heat of fusion and the melting point of lead are 2.45 × 104 j/kg and 327°c, respectively.)