Increase £1.20 by a quarter(1/4)

Which expression can be used to determine the slope of the line that passes through the points -6, three and one, -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?

Ab and bc form a right angle at point b. if a= (-3,-1) and b= (4,4) what is the equation of bc?