Answer: 1.67 kg
Explanation:
The quantity of heat required to raise the temperature of a substance by one degree Celsius is called the specific heat capacity.

Q = Heat absorbed=
=
(1kJ=1000J)
m= mass of substance = ?
c = specific heat capacity = 
Change in temperature ,
Putting in the values, we get:

(1kg=1000g)
Thus the mass (in kg) of the copper sample is 1.67
Explanation:
in the case of blood loss, you need blood from someone with your blood type or with universal donor type
Answer: Polythene
Polythene is a synthetic polymer classified as plastics.
Explanation:
Polythene is formed artificially from several repeating units of ethene molecules (monomers) in a reaction known as polymerization.
The polyethene can be represented as [CH2-CH2]n, where n is thousands to ten thousands unit of ethene.
It is used to make
- plastic bags,
- cable insulators
- plastic crates etc
Thus, polythene is a synthetic polymer of ethene, and classified as plastics.