Estimating the luminosity class of an m star is much more important than measuring it for an o star if you are determining the distance to that star. why is that the case?

Astudent is working in the lab to determine how time affect impulse the student keeps the force the same in each row but changes impact the time some data is shown witch trial has the greatest a student is working in the lab to determine how time affect impulse the student keeps the fours the same in each row but change is the impact time some data shown witch trial has the greatest impulse

Choose the most likely outcome of this scenario: jen decided to go bike riding without a helmet. while no one is around during her ride, she is thrown from her bike when her wheel goes into a pothole. she is not injured, but she is terrified to get back on her bike. what happens next? a. her physical health is affected even though she wasn't hurt. b. her mental and emotional health are affected because she is afraid to get back on her bike. c. her social health is affected because she is worried her friends saw the fall. d. her overall health is not affected at all by her fall.

Aresistor with an unknown resistance is connected in parallel to a 9 ω resistor. when both resistors are connected in parallel to an emf source of 21 v, the current through the unknown resistor is measured with an ammeter to be 4 a. what is the resistance of the unknown resistor? answer in units of ω.