Nearly the end of school, how are you feeling?​

Aflower has 26 chromosomes. to create a new flower,how many would a sperm cell have what is called?

Can someone factor this fully? my friend and i have two different answers and i would like to know if either of them is right. you in advance. a^2 - b^2 + 25 + 10a

What is the interquartile range of this data set? 2, 5, 9, 11, 18, 30, 42, 48, 55, 73, 81