Determining the dates of old objects using radioactive elements is called dating?

An object moves from position +34m to the position -15m in 15 seconds. what is the total displacement? what is the total velocity?

Light traveling in water, nwater = 1.33, strikes a plastic block at an angle of incidence of 51.4°; part of the beam is reflected and part is refracted. if the index of refraction of the plastic is 2.0, what is the angle made by the reflected and refracted beams?

Multiply or divide to make this english distance conversion. 174 inches = feet (14.5, 58, 2,088, 23)