1. red blood cells
2. diploid is a type of cell with two sets of chromosomes (usually from the mother and farther)
haploid is a sex cell, so it is a cell with a single set of chromosomes (egg and sperm cells)
Cool front is not a standard weather front. Cold front, warm front and occluded front are all standard weather front. When you say weather front, it is a boundary that separate 2 air masses.
