What is a critical mass of uranium 235

Jason is a body builder. despite being more fit, he weighs more than his brother ryan, who is the same height. which is a possible reason? a. jason has more muscle mass than ryan does. b. jason has more body fat than ryan does. c. jason has more muscle mass and body fat than ryan does d. jason has less body fat than ryan does.

Light traveling in a medium with a refractive index 1.19 is incident on a plate of another medium with index of refraction 1.79. at what angle of incidence is the reflected light fully polarized?

What is the average speed of a car that travels 40 mph for 1 hour and 60 mph in another hour?