Which of the following groups of elements is ranked from least reactive to most reactive?
A. Sr, Ca, Mg, Be
B. K, Na, Li, H
C. Li, Na, K, Rb
D. K, Ca, Sc, Ti

Arod of some material 0.20 m long elongates 0.20 mm on heating from 21 to 120°c. determine the value of the linear coefficient of thermal expansion [in (degrees c)^-1] for this material.

Write the correct abbreviation for each metric unit

Unpolarized light whose intensity is 1.19 w/ is incident on a polarizer. (a) what is the intensity of the light leaving the polarizer? (b) if the analyzer is set at an angle of = 41.0∘ with respect to the polarizer, what is the intensity of the light that reaches the photocell?