When you stifle a sneeze, you can damage delicate tissues because the pressure of the air that is not allowed to escape may rise by up to 45 kPa. If this extra pressure acts on the inside of your 8.4-mm-diameter eardrum, what is the outward force

The outward force is 5934.6N.

Explanation: Pressure is force per area. As the eardrum is a circular organ and has 4.2·m of radius, the area of the organ will be:

Area = π·r²

Area = 3.14·(4.2.)²

Area = 13.2·m²

To calculate force:

P = F/A

F = P·A

F = 45.·13.2·

F = 5934.6N

The outward force is F=5934.6N.

Polyploidy (more than two complete sets of chromosomes) is not rare among plants. For example, pollen grains may reach female flowers via animals or wind. In some cases, pollen grains from species with 4 complete sets of chromosomes will have 2 sets of chromosomes. Pollen grains may fuse with a female reproductive organ with 1 set of chromosome (so, female plant must have 2 sets of chromosomes). The resulting zygote will have 2 + 1 sets of chromosomes, so the plant will have 3 complete sets of chromosomes.