Anyone HELP I WILL GIVE BRAINLIEST - its my sisters and i forgot everything in math shes in grade 9

Aflower has 26 chromosomes. to create a new flower, how many chromosomes would a sperm cell have? what is this process called? part 2: within a flower cell that has 26 chromosomes, how many chromosomes would a cell that is created within the stem of a flower as it grows, have? what is this process called?

Asystem of equations has 1 solution.if 4x-y=5 is one of the equations , which could be the other equation ?

Three numbers x, y, and z are in the ratio 2: 7: 8. if 12 is subtracted from y, then three numbers form a geometric sequence (in the order x, y–12, z). find x, y, and z. there are 2 sets.