If an object is 150 light years away, how long will it take for the light to get to you

In science and physics what is the standard unit of measure for speed?

Two point charges are separated by a certain distance. how does the strength of the electric field produced by the first charge, at the position of the second charge, change if the second charge is doubled? a. the field does not change b. the field strength decreases by half. c. the field strength doubles d. the field strength quadruples

Heterogeneous mixture with larger particles that never settle is