Answer:
a.
Everyone in the Discrete Math class
Everyone in the city
b.
People who receive their pension contribution
Students in a kindergarten class
c.
Twins in the world
Everyone in the world
d.
Miley Cyrus and Dua Lipa
Two blood brothers
Step-by-step explanation:
What we will do is go through each statement and we will give it a true domain and a false domain:
a.) Everyone is studying discrete mathematics.
Domain true = {Everyone in the Discrete Math class}
True because they belong to the math group
Domain false = {Everyone in the city}
False because in the city not everyone gives this type of mathematics.
b.) Everyone is older than 21 years.
Domain true = {People who receive their pension contribution}
True because to receive a pension you have to work for many years.
Domain false = {Students in a kindergarten class}
False because at 21 years old I shouldn't be in kindergarten anymore
c.) Every two people have the same mother.
True domain = {Twins in the world}
True because the twins have the same mother.
Domain false = {Everyone in the world}
False because not everyone has the same mother
d.) No two different people have the same grandmother.
True domain = {Miley Cyrus and Dua Lipa}
True because Miley and Dua don't have the same grandmother
Domain 2 = {Two blood brothers}
False because two blood brothers have the same grandmother
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