1. Explain how immunizations work to protect the body against pathogens and antigens. Refer to B- cells and T-cells in your answer. Discuss how and why science would need to find a way to
discourage thymus atrophy if human life is ever to expand beyond around 120 years.

Photoelectrons with a maximum speed of 6.50 x 107 m/s are ejected from a surface in the presence of light with a frequency of 6.75 x 1014hz. if the mass of an electron is 9.10 x 10-31 kg, calculate in joules the maximum kinetic energy of a single electron. 3.84 x 10-15 j 1.92 x 10-15 j 5.92 x 10-23 j 3.07 x 10-16 j

The mass of a bowling ball is 10 kg and the mass of a ping pong ball is 0.015 kg. if the two objects are 5 meters apart, what is the gravitational force ?

Which model displays the change in a gas when the temperature of the gaseous system decreases?