Plant a and plant b are heterozygous for a gene that expresses their tall trait (tt). upon crossing, what is expected in the offspring, assuming random chromosome segregation?

The answer is 75% of offspring will be tall and 25% of offspring will be short.

If:
T - the dominant allele for tall trait
t - the recessive allele for short trait

Then:
TT - dominant homozygote (tall)
Tt - heterozygote (tall)
tt - recessive homozygote (short).

In the cross of two heterozygotes Tt x Tt 75% of offspring will be tall and 25% of offspring will be short:

Parental generation:        Tt     x     Tt
Offspring generation:   TT    Tt    Tt    tt

Thus, 3 out of 4 (=3/4=75%) offspring are tall (1 TT and 2 Tt) and 1 out of 4 (=1/4=25%) offspring is short. Speaking of genotypes, 1 out of 4 (=1/4=25%) is dominant homozygote (TT), 2 out of 4 (=2/4=50%) is heterozygote (Tt), and 1 out of 4 (=1/4=25%) is recessive homozygote (tt).

What is the question? if you were looking to design a method of separating something, you can separate this compound by putting both in water and allowing the water to dissolve the sugar. then pour it into another beaker and evaporate it then boom! salt and sugar : )